Principle of inclusion exclusion - Inclusion-Exclusion Selected Exercises Powerpoint Presentation taken from Peter Cappello’s webpage www.cs.ucsb.edu/~capello

 
For example, the number of multiples of three below 20 is [19/3] = 6; these are 3, 6, 9, 12, 15, 18. 33 = [999/30] numbers divisible by 30 = 2·3·. According to the Inclusion-Exclusion Principle, the amount of integers below 1000 that could not be prime-looking is. 499 + 333 + 199 - 166 - 99 - 66 + 33 = 733. There are 733 numbers divisible by ... . How much does dillard

A general "inclusion-exclusion principle" / Formulas like $\inf(a,b)\sup(a,b)=ab$ 3 Coupon collector's problem: mean and variance in number of coupons to be collected to complete a set (unequal probabilities)Number of solutions to an equation using the inclusion-exclusion principle 3 Given $3$ types of coins, how many ways can one select $20$ coins so that no coin is selected more than $8$ times. Using inclusion-exclusion principle to count the integers in $\{1, 2, 3, \dots , 100\}$ that are not divisible by $2$, $3$ or $5$ Ask Question The Inclusion-Exclusion Principle (for two events) For two events A, B in a probability space: P(A ...Lecture 4: Principle of inclusion and exclusion Instructor: Jacob Fox 1 Principle of inclusion and exclusion Very often, we need to calculate the number of elements in the union of certain sets. Assuming that we know the sizes of these sets, and their mutual intersections, the principle of inclusion and exclusion allows us to do exactly that. Apr 9, 2016 · For each triple of primes p 1, p 2, p 3, the number of integers less than or equal to n that share a factors of p 1, p 2, and p 3 with n is n p 1 p 2 p 3. And so forth. Therefore, using Inclusion-Exclusion, the number of integers less than or equal to n that share a prime factor with n would be. ∑ p ∣ n n p − ∑ p 1 < p 2 ∣ n n p 1 p 2 ... The principle of inclusion and exclusion is very important and useful for enumeration problems in combinatorial theory. By using this principle, in the chapter, the number of elements of A that satisfy exactly r properties of P are deduced, given the numbers of elements of A that satisfy at least k ( k ≥ r) properties of P.Mar 28, 2022 · The principle of Inclusion-Exclusion is an effective way to calculate the size of the individual set related to its union or capturing the probability of complicated events. Takeaways Inclusion and exclusion criteria increases the likelihood of producing reliable and reproducible results. the static version of the distinction inclusion/exclusion for addressing the emergence of new inequalities (section IV). On this basis, section V proposes an original classification of different constellations of inclusion/exclusion and illustrates them with specific examples. Section VI offers a summary of the main findings together withMar 8, 2020 · The principle of inclusion-exclusion is an important result of combinatorial calculus which finds applications in various fields, from Number Theory to Probability, Measurement Theory and others. In this article we consider different formulations of the principle, followed by some applications and exercises. Nov 4, 2021 · The inclusion-exclusion principle is similar to the pigeonhole principle in that it is easy to state and relatively easy to prove, and also has an extensive range of applications. These sort of ... You can set up an equivalent question. Subtract out 4 4 from both sides so that 0 ≤x2 ≤ 5 0 ≤ x 2 ≤ 5. Similarly, subtract out 7 7 so 0 ≤ x3 ≤ 7 0 ≤ x 3 ≤ 7. This leaves us with x1 +x2 +x3 = 7 x 1 + x 2 + x 3 = 7. We can use a generating function to give us our inclusion-exclusion formula.The principle of inclusion and exclusion is very important and useful for enumeration problems in combinatorial theory. By using this principle, in the chapter, the number of elements of A that satisfy exactly r properties of P are deduced, given the numbers of elements of A that satisfy at least k ( k ≥ r) properties of P.Apr 17, 2016 · You might take out those divisible by $2,3,5,7$ (all the primes up to $\sqrt{100}$). Doing this is a pretty straightforward includsion-exclusion counting, and this has the effect of counting the number of primes between $10$ and $100$. Last post was a proof for the Inclusion-Exclusion Principle and now this post is a couple of examples using it. The first example will revisit derangements (first mentioned in Power of Generating Functions); the second is the formula for Euler's phi function. Yes, many posts will end up mentioning Euler …Inclusion/Exclusion with 4 Sets • Suppose you are using the inclusion-exclusion principle to compute the number of elements in the union of four sets. –Each set has 15 elements. –The pair-wise intersections have 5 elements each. –The three-way intersections have 2 elements each. –There is only one element in the intersection of all ... The way I usually think of the Inclusion-Exclusion Principle goes something like this: If something is in n of the S j, it will be counted ( n k) times in the sum of the sizes of intersections of k of the S j. Therefore, it will be counted. (1) ∑ k ≥ 1 ( − 1) k − 1 ( n k) = 1. time in the expression.Number of solutions to an equation using the inclusion-exclusion principle 3 Given $3$ types of coins, how many ways can one select $20$ coins so that no coin is selected more than $8$ times. The Restricted Inclusion-Exclusion Principle. Let be subsets of . Then. This is a formula which looks familiar to many people, I'll call it The Restricted Inclusion-Exclusion Principle, it can convert the problem of calculating the size of the union of some sets into calculating the size of the intersection of some sets. The principle of inclusion and exclusion is intimately related to Möbius inversion, which can be generalized to posets. I'd start digging in this general area. I'd start digging in this general area.This formula makes sense to me again, but can someone please explain it to me in simple terms how the binomial theorem is even related to inclusion/exclusion? I've also seen proofs where examples substitute the x = 1 and y = -1 and we end up getting the binomial expansion to equal 0. I just don't see how we can relate that to PIE. Please help ...The inclusion exclusion principle forms the basis of algorithms for a number of NP-hard graph partitioning problems, such as graph coloring. A well known application of the principle is the construction of the chromatic polynomial of a graph. Bipartite graph perfect matchings This proves the principle of inclusion-exclusion. Although the proof seems very exciting, I am confused because what the author has proved is $1=1$ from the LHS and RHS. Thus, is this still a valid proof? We need to prove that the total cardinality of LHS is the RHS. The RHS produces a $1$ for each member of the union of the sets.Inclusion/Exclusion with 4 Sets • Suppose you are using the inclusion-exclusion principle to compute the number of elements in the union of four sets. –Each set has 15 elements. –The pair-wise intersections have 5 elements each. –The three-way intersections have 2 elements each. –There is only one element in the intersection of all ...The principle of inclusion and exclusion is very important and useful for enumeration problems in combinatorial theory. By using this principle, in the chapter, the number of elements of A that satisfy exactly r properties of P are deduced, given the numbers of elements of A that satisfy at least k ( k ≥ r) properties of P.For example, the number of multiples of three below 20 is [19/3] = 6; these are 3, 6, 9, 12, 15, 18. 33 = [999/30] numbers divisible by 30 = 2·3·. According to the Inclusion-Exclusion Principle, the amount of integers below 1000 that could not be prime-looking is. 499 + 333 + 199 - 166 - 99 - 66 + 33 = 733. There are 733 numbers divisible by ...A thorough understanding of the inclusion-exclusion principle in Discrete Mathematics is vital for building a solid foundation in set theory. With the inclusion-exclusion principle, there are generally two types of questions that appear in introductory and lower level Discrete Mathematics syllabi. These question types are:The principle of inclusion and exclusion is very important and useful for enumeration problems in combinatorial theory. By using this principle, in the chapter, the number of elements of A that satisfy exactly r properties of P are deduced, given the numbers of elements of A that satisfy at least k ( k ≥ r) properties of P.Nov 21, 2018 · A thorough understanding of the inclusion-exclusion principle in Discrete Mathematics is vital for building a solid foundation in set theory. With the inclusion-exclusion principle, there are generally two types of questions that appear in introductory and lower level Discrete Mathematics syllabi. These question types are: Homework Statement Suppose that p and q are prime numbers and that n = pq. Use the principle of inclusion-exclusion to find the number of positive integers not exceeding n that are relatively prime to n. Homework Equations Inclusion-Exclusion The Attempt at a Solution The...inclusion-exclusion principle integers modulo n. 1. Proof of Poincare's Inclusion-Exclusion Indicator Function Formula by Induction. 5. Why are there $2^n-1$ terms in ...The way I usually think of the Inclusion-Exclusion Principle goes something like this: If something is in n of the S j, it will be counted ( n k) times in the sum of the sizes of intersections of k of the S j. Therefore, it will be counted. (1) ∑ k ≥ 1 ( − 1) k − 1 ( n k) = 1. time in the expression.In order to practice the Inclusion–exclusion principle and permutations / derangements, I tried to develop an exercise on my own. Assume there are $6$ players throwing a fair die with $6$ sides. In this game, player 1 is required to throw a 1, player 2 is required to throw a 2 and so on.This video contains the description about principle of Inclusion and ExclusionSep 14, 2018 · This formula makes sense to me again, but can someone please explain it to me in simple terms how the binomial theorem is even related to inclusion/exclusion? I've also seen proofs where examples substitute the x = 1 and y = -1 and we end up getting the binomial expansion to equal 0. I just don't see how we can relate that to PIE. Please help ... 1 Answer. It might be useful to recall that the principle of inclusion-exclusion (PIE), at least in its finite version, is nothing but the integrated version of an algebraic identity involving indicator functions. 1 −1A =∏i=1n (1 −1Ai). 1 − 1 A = ∏ i = 1 n ( 1 − 1 A i). Integrating this pointwise identity between functions, using ...Due to the duality between union and intersection, the inclusion–exclusion principle can be stated alternatively in terms of unions or intersections. Feb 24, 2014 at 15:36. You could intuitively try to prove an equation by drawing four sets in the form of a Venn diagram -- say A1,A2,A3,A4 A 1, A 2, A 3, A 4, and observing the intersections between the circles. You want to find the cardinality of the union.Sep 24, 2015 · How to count using the Inclusion/Exclusion Principle. This is Chapter 9 Problem 4 of the MATH1231/1241 Algebra notes. Presented by Daniel Chan from UNSW. Notes on the Inclusion Exclusion Principle The Inclusion Exclusion Principle Suppose that we have a set S consisting of N distinct objects. Let A1; A2; :::; Am be a set of properties that the objects of the set S may possess, and let N(Ai) be the number of objects having property Ai: NoteApr 21, 2015 · The inclusion-exclusion principle states that the number of elements in the union of two given sets is the sum of the number of elements in each set, minus the number of elements that are in both sets. Nov 21, 2018 · A thorough understanding of the inclusion-exclusion principle in Discrete Mathematics is vital for building a solid foundation in set theory. With the inclusion-exclusion principle, there are generally two types of questions that appear in introductory and lower level Discrete Mathematics syllabi. These question types are: Notes on the Inclusion Exclusion Principle The Inclusion Exclusion Principle Suppose that we have a set S consisting of N distinct objects. Let A1; A2; :::; Am be a set of properties that the objects of the set S may possess, and let N(Ai) be the number of objects having property Ai: Note1 Principle of inclusion and exclusion Very often, we need to calculate the number of elements in the union of certain sets. Assuming that we know the sizes of these sets, and their mutual intersections, the principle of inclusion and exclusion allows us to do exactly that. Suppose that you have two sets A; B.Mar 28, 2022 · The principle of Inclusion-Exclusion is an effective way to calculate the size of the individual set related to its union or capturing the probability of complicated events. Takeaways Inclusion and exclusion criteria increases the likelihood of producing reliable and reproducible results. Prove the following inclusion-exclusion formula. P ( ⋃ i = 1 n A i) = ∑ k = 1 n ∑ J ⊂ { 1,..., n }; | J | = k ( − 1) k + 1 P ( ⋂ i ∈ J A i) I am trying to prove this formula by induction; for n = 2, let A, B be two events in F. We can write A = ( A ∖ B) ∪ ( A ∩ B), B = ( B ∖ A) ∪ ( A ∩ B), since these are disjoint ...I want to find the number of primes numbers between 1 and 30 using the exclusion and inclusion principle. This is what I got: The numbers in sky-blue are the ones I have to subtract.The principle of inclusion-exclusion was used by Nicholas Bernoulli to solve the recontres problem of finding the number of derangements (Bhatnagar 1995, p. 8). For example, for the three subsets , , and of , the following table summarizes the terms appearing the sum.Theorem 7.7. Principle of Inclusion-Exclusion. The number of elements of X X which satisfy none of the properties in P P is given by. ∑S⊆[m](−1)|S|N(S) ∑ S ⊆ [ m] ( − 1) | S | N ( S). This page titled 7.2: The Inclusion-Exclusion Formula is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Mitchel T ...the static version of the distinction inclusion/exclusion for addressing the emergence of new inequalities (section IV). On this basis, section V proposes an original classification of different constellations of inclusion/exclusion and illustrates them with specific examples. Section VI offers a summary of the main findings together withIt follows that the e k objects with k of the properties contribute a total of ( k m) e k to e m and hence that. (1) s m = ∑ k = m r ( k m) e k. Now I’ll define two polynomials: let. S ( x) = ∑ k = 0 r s k x k and E ( x) = ∑ k = 0 r e k x k. In view of ( 1) we have.Mar 26, 2020 · Inclusion-exclusion principle question - 3 variables. There are 3 types of pants on sale in a store, A, B and C respectively. 45% of the customers bought pants A, 35% percent bought pants B, 30% bought pants C. 10% bought both pants A & B, 8% bought both pants A & C, 5% bought both pants B & C and 3% of the customers bought all three pairs. Principle of Inclusion and Exclusion is an approach which derives the method of finding the number of elements in the union of two finite sets. This is used to solve combinations and probability problems when it is necessary to find a counting method, which makes sure that an object is not counted twice. Consider two finite sets, A and B.Full Course of Discrete Mathematics: https://youtube.com/playlist?list=PLV8vIYTIdSnZjLhFRkVBsjQr5NxIiq1b3In this video you can learn about Principle of Inclu... Mar 26, 2020 · Inclusion-exclusion principle question - 3 variables. There are 3 types of pants on sale in a store, A, B and C respectively. 45% of the customers bought pants A, 35% percent bought pants B, 30% bought pants C. 10% bought both pants A & B, 8% bought both pants A & C, 5% bought both pants B & C and 3% of the customers bought all three pairs. University of Pittsburgh Using inclusion-exclusion principle to find the probability of events. 2. Find the correspondence between natural numbers and subsets with the inclusion-exclusion ...It follows that the e k objects with k of the properties contribute a total of ( k m) e k to e m and hence that. (1) s m = ∑ k = m r ( k m) e k. Now I’ll define two polynomials: let. S ( x) = ∑ k = 0 r s k x k and E ( x) = ∑ k = 0 r e k x k. In view of ( 1) we have.The Inclusion-Exclusion Principle. From the First Principle of Counting we have arrived at the commutativity of addition, which was expressed in convenient mathematical notations as a + b = b + a. The Principle itself can also be expressed in a concise form. It consists of two parts. The first just states that counting makes sense. Principle of Inclusion and Exclusion is an approach which derives the method of finding the number of elements in the union of two finite sets. This is used to solve combinations and probability problems when it is necessary to find a counting method, which makes sure that an object is not counted twice. Consider two finite sets, A and B.It seems that this formula is similar to an inclusion-exclusion formula? One approach I was thinking was an induction approach. Obviously if we take $|K|=1$ the formula holds. The induction step could be to assume it holds for $|K-1|-1$ and then simply prove the final result. Does this seem a viable approach, any other suggested approaches are ...TheInclusion-Exclusion Principle Physics 116C Fall 2012 TheInclusion-Exclusion Principle 1. The probability that at least one oftwoevents happens Consider a discrete sample space Ω. We define an event A to be any subset of Ω, which in set notation is written as A⊂ Ω. Then, Boas asserts in eq. (3.6) on p. 732 that1The inclusion-exclusion principle is a combinatorial method for determining the cardinality of a set where each element XU satisfies a list of properties . In this paper we will display the ...You can set up an equivalent question. Subtract out 4 4 from both sides so that 0 ≤x2 ≤ 5 0 ≤ x 2 ≤ 5. Similarly, subtract out 7 7 so 0 ≤ x3 ≤ 7 0 ≤ x 3 ≤ 7. This leaves us with x1 +x2 +x3 = 7 x 1 + x 2 + x 3 = 7. We can use a generating function to give us our inclusion-exclusion formula.The lesson accompanying this quiz and worksheet called Inclusion-Exclusion Principle in Combinatorics can ensure you have a quality understanding of the following: Description of basic set theory ... The Inclusion-Exclusion Principle. From the First Principle of Counting we have arrived at the commutativity of addition, which was expressed in convenient mathematical notations as a + b = b + a. The Principle itself can also be expressed in a concise form. It consists of two parts. The first just states that counting makes sense.TheInclusion-Exclusion Principle Physics 116C Fall 2012 TheInclusion-Exclusion Principle 1. The probability that at least one oftwoevents happens Consider a discrete sample space Ω. We define an event A to be any subset of Ω, which in set notation is written as A⊂ Ω. Then, Boas asserts in eq. (3.6) on p. 732 that1Number of solutions to an equation using the inclusion-exclusion principle 3 Given $3$ types of coins, how many ways can one select $20$ coins so that no coin is selected more than $8$ times. Mar 8, 2020 · The principle of inclusion-exclusion is an important result of combinatorial calculus which finds applications in various fields, from Number Theory to Probability, Measurement Theory and others. In this article we consider different formulations of the principle, followed by some applications and exercises. It seems that this formula is similar to an inclusion-exclusion formula? One approach I was thinking was an induction approach. Obviously if we take $|K|=1$ the formula holds. The induction step could be to assume it holds for $|K-1|-1$ and then simply prove the final result. Does this seem a viable approach, any other suggested approaches are ...The inclusion exclusion principle forms the basis of algorithms for a number of NP-hard graph partitioning problems, such as graph coloring. A well known application of the principle is the construction of the chromatic polynomial of a graph. Bipartite graph perfect matchingsThe Restricted Inclusion-Exclusion Principle. Let be subsets of . Then. This is a formula which looks familiar to many people, I'll call it The Restricted Inclusion-Exclusion Principle, it can convert the problem of calculating the size of the union of some sets into calculating the size of the intersection of some sets. Aug 31, 2019 · It seems that this formula is similar to an inclusion-exclusion formula? One approach I was thinking was an induction approach. Obviously if we take $|K|=1$ the formula holds. The induction step could be to assume it holds for $|K-1|-1$ and then simply prove the final result. Does this seem a viable approach, any other suggested approaches are ... The Inclusion-Exclusion Principle. From the First Principle of Counting we have arrived at the commutativity of addition, which was expressed in convenient mathematical notations as a + b = b + a. The Principle itself can also be expressed in a concise form. It consists of two parts. The first just states that counting makes sense. 排容原理. 三個集的情況. 容斥原理 (inclusion-exclusion principle)又称 排容原理 ,在 組合數學 裏,其說明若 , ..., 為 有限集 ,則. 其中 表示 的 基數 。. 例如在兩個集的情況時,我們可以通過將 和 相加,再減去其 交集 的基數,而得到其 并集 的基數。. The Inclusion-Exclusion Principle. From the First Principle of Counting we have arrived at the commutativity of addition, which was expressed in convenient mathematical notations as a + b = b + a. The Principle itself can also be expressed in a concise form. It consists of two parts. The first just states that counting makes sense. The principle of inclusion and exclusion was used by the French mathematician Abraham de Moivre (1667–1754) in 1718 to calculate the number of derangements on n elements. Since then, it has found innumerable applications in many branches of mathematics.Counting intersections can be done using the inclusion-exclusion principle only if it is combined with De Morgan’s laws of complementing. a) true. b) false. View Answer. 10. Using the inclusion-exclusion principle, find the number of integers from a set of 1-100 that are not divisible by 2, 3 and 5. a) 22. b) 25. c) 26.This proves the principle of inclusion-exclusion. Although the proof seems very exciting, I am confused because what the author has proved is $1=1$ from the LHS and RHS. Thus, is this still a valid proof? We need to prove that the total cardinality of LHS is the RHS. The RHS produces a $1$ for each member of the union of the sets.University of PittsburghNotes on the Inclusion Exclusion Principle The Inclusion Exclusion Principle Suppose that we have a set S consisting of N distinct objects. Let A1; A2; :::; Am be a set of properties that the objects of the set S may possess, and let N(Ai) be the number of objects having property Ai: Note Lecture 4: Principle of inclusion and exclusion Instructor: Jacob Fox 1 Principle of inclusion and exclusion Very often, we need to calculate the number of elements in the union of certain sets. Assuming that we know the sizes of these sets, and their mutual intersections, the principle of inclusion and exclusion allows us to do exactly that. The principle of inclusion and exclusion is intimately related to Möbius inversion, which can be generalized to posets. I'd start digging in this general area. I'd start digging in this general area.Nov 21, 2018 · A thorough understanding of the inclusion-exclusion principle in Discrete Mathematics is vital for building a solid foundation in set theory. With the inclusion-exclusion principle, there are generally two types of questions that appear in introductory and lower level Discrete Mathematics syllabi. These question types are: The inclusion exclusion principle forms the basis of algorithms for a number of NP-hard graph partitioning problems, such as graph coloring. A well known application of the principle is the construction of the chromatic polynomial of a graph. Bipartite graph perfect matchings The Inclusion-Exclusion Principle (for two events) For two events A, B in a probability space: P(A ...The principle of inclusion and exclusion (PIE) is a counting technique that computes the number of elements that satisfy at least one of several properties while guaranteeing that elements satisfying more than one property are not counted twice. The principle of inclusion and exclusion is very important and useful for enumeration problems in combinatorial theory. By using this principle, in the chapter, the number of elements of A that satisfy exactly r properties of P are deduced, given the numbers of elements of A that satisfy at least k ( k ≥ r) properties of P.

The inclusion and exclusion (connection and disconnection) principle is mainly known from combinatorics in solving the combinatorial problem of calculating all permutations of a finite set or .... Trucks for sale near me under dollar2000

principle of inclusion exclusion

The inclusion-exclusion principle states that the number of elements in the union of two given sets is the sum of the number of elements in each set, minus the number of elements that are in both sets.TheInclusion-Exclusion Principle Physics 116C Fall 2012 TheInclusion-Exclusion Principle 1. The probability that at least one oftwoevents happens Consider a discrete sample space Ω. We define an event A to be any subset of Ω, which in set notation is written as A⊂ Ω. Then, Boas asserts in eq. (3.6) on p. 732 that1Theorem 7.7. Principle of Inclusion-Exclusion. The number of elements of X X which satisfy none of the properties in P P is given by. ∑S⊆[m](−1)|S|N(S) ∑ S ⊆ [ m] ( − 1) | S | N ( S). This page titled 7.2: The Inclusion-Exclusion Formula is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Mitchel T ...By the principle of inclusion-exclusion, jA[B[Sj= 3 (219 1) 3 218 + 217. Now for the other solution. Instead of counting study groups that include at least one of Alicia, Bob, and Sue, we will count study groups that don’t include any of Alicia, Bob, or Sue. To form such a study group, we just need to choose at least 2 of the remaining 17 ... Inclusion-Exclusion and its various Applications. In the field of Combinatorics, it is a counting method used to compute the cardinality of the union set. According to basic Inclusion-Exclusion principle : For 2 finite sets and , which are subsets of Universal set, then and are disjoint sets. .inclusion-exclusion principle integers modulo n. 1. Proof of Poincare's Inclusion-Exclusion Indicator Function Formula by Induction. 5. Why are there $2^n-1$ terms in ...By the principle of inclusion-exclusion, jA[B[Sj= 3 (219 1) 3 218 + 217. Now for the other solution. Instead of counting study groups that include at least one of Alicia, Bob, and Sue, we will count study groups that don’t include any of Alicia, Bob, or Sue. To form such a study group, we just need to choose at least 2 of the remaining 17 ... How to count using the Inclusion/Exclusion Principle. This is Chapter 9 Problem 4 of the MATH1231/1241 Algebra notes. Presented by Daniel Chan from UNSW.The inclusion exclusion principle forms the basis of algorithms for a number of NP-hard graph partitioning problems, such as graph coloring. A well known application of the principle is the construction of the chromatic polynomial of a graph. Bipartite graph perfect matchings It follows that the e k objects with k of the properties contribute a total of ( k m) e k to e m and hence that. (1) s m = ∑ k = m r ( k m) e k. Now I’ll define two polynomials: let. S ( x) = ∑ k = 0 r s k x k and E ( x) = ∑ k = 0 r e k x k. In view of ( 1) we have.The Inclusion-Exclusion Principle can be used on A n alone (we have already shown that the theorem holds for one set): X J fng J6=; ( 1)jJj 1 \ i2 A i = ( 1)jfngj 1 \ The inclusion-exclusion principle (like the pigeon-hole principle we studied last week) is simple to state and relatively easy to prove, and yet has rather spectacular applications. In class, for instance, we began with some examples that seemed hopelessly complicated..

Popular Topics