... numbers than most of us canimagine. However in discretemathematics we often work with functions from a finite setS with s elements to a finite set T with t elements. Then there are only a finite ... original formula for q. Recall that our proof of the formula we had inExercise 1.4-5 did not explain why the product of three factorials appeared in the denominator,it simply proved the formula ... the formula was correct. With this idea in hand, we could now explain why theproduct in the denominator of the formula in Exercise 1.4-5 for the number of labellings with three labels is what...
... n:• If student 0 gets candy, then student 1 also gets candy.• If student 1 gets candy, then student 2 also gets candy.• If student 2 gets candy, then student 3 also gets candy, and so forth.Now ... are student 17. By these rules, are you entitled to a miniature candybar? Well, student 0 gets candy by the first rule. Therefore, by the second rule, student 1 also gets candy, which means student ... proof toanyone who disagrees with you.Intimidation. Truth is asserted by someone with whom disagrement seems unwise. Mathematics its own notion of “proof”. In mathematics, a proof is a verification...
... — page i — #1 Mathematics forComputer Science revised Thursday 10thJanuary, 2013, 00:28Eric LehmanGoogle Inc.F Thomson LeightonDepartment of Mathematics and the ComputerScience and AI ... proposition for eachpossible set of truth values for the variables. For example, the truth table for theproposition “P AND Q” has four lines, since there are four settings of truth values for the ... or nota T ever appears, but as with testing validity, this approach quickly bogs down for formulas with many variables because truth tables grow exponentially with thenumber of variables.Is...
... defined for SO = ao;all n 3 0 .)S, = S-1 + a,, for n > 0.(2.6)Therefore we can evaluate sums in closed form by using the methods welearned in Chapter 1 to solve recurrences in closed form. For ... 3These two inequalities, together with the trivial solution for n = 0, yieldTo =O;T, = 2T+1 +l , for n > 0.(1.1)(Notice that these formulas are consistent with the known values TI = ... much happier. That is, we’d like a nice, neat,“closed form” for T,, that lets us compute it quickly, even for large n. With a closed form, we can understand what T,, really is.So how do...
... exponents for rising factorial powers, analogous to(2.52)? Use this to define XC”.10The text derives the following formula for the difference of a product:A(uv) = uAv + EvAu.How can this formula ... different form, n = [n/21 + [n/2].If we had wanted the parts to be in nondecreasing order, with the smallgroups coming before the larger ones, we could have proceeded in the sameway but with [n/mJ ... circle.34 Let f(n) = Et=, [lgkl.Find a closed form for f(n) , when n 3 1.L Provethatf(n)=n-l+f([n/2~)+f(~n/Z])foralln~l.35Simplify the formula \(n + 1 )‘n! e] mod n.Simplify it, but36...
... (mod 4).QED for the case m = 12.QED: Quite EasilySo far we’ve proved our congruence for prime m, for m = 4, and for m =Done.12. Now let’s try to prove it for prime powers. For concreteness ... fractionsm/n with m > 0 and n 6 N (including fractions that are not reduced).It is defined recursively by starting with For N > 1, we form ?$,+I by inserting two symbols just before the kNthsymbol ... with entire equations, for which a slightly differentnotation is more convenient:a s b (mod m)amodm = bmodm.(4.35) For example, 9 = -16 (mod 5), because 9 mod 5 = 4 = (-16) mod 5. Theformula...
... harder to start with f(k)and to figure out its indefinite sum x f(k) 6k = g(k) + C; this function gmight not have a simple form. For example, there is apparently no simpleform for x (E) ... every closed form for hypergeometricsleads to additional closed forms and to additional entries in the database. For example, the identities in exercises 25 and 26 tell us how to transform onehypergeometric ... > 2m. Therefore this limit gives us exactly thesum (5.20) we began with. 5.6 HYPERGEOMETRIC TRANSFORMATIONSIt should be clear by now that a database of known hypergeometricclosed forms is a...
... haven’t come up with a closed formula for them. We haven’t foundclosed forms for Stirling numbers, Eulerian numbers, or Bernoulli numberseither; but we were able to discover the closed form H, ... NUMBERSBefore we stop to marvel at our derivation, we should check its accuracy. For n = 0 the formula correctly gives Fo = 0; for n = 1, it gives F1 =(+ - 9)/v%, which is indeed 1. For higher ... (-l).", for n > 0.(6.103)When n = 6, for example, Cassini’s identity correctly claims that 1 3.5-tS2 = 1.A polynomial formula that involves Fibonacci numbers of the form F,,+k for small...
... consider the subfields within an area of study than it is to define the area ofstudy. So it is withcomputer science. 1.1 What Is Computer Science? In some respects, computerscience is a new discipline; ... of computerscience is computer programming.Some people prefer the term used in many European languages, informatics, overwhat is called computerscience in the United States. Computerscience ... departments of computer science. But computer science has benefited from work done in such older disciplines as mathematics, psychology,electricalengineering, physics, andlinguistics. Computer science...
... 170Introduction to Programming3Computers have a fixed set of instructions that they can perform for us. The specificinstruction set depends upon the make and model of a computer. However, these instructions ... that the computer always attempts to do precisely what you tell it to do. Say, for example, you tell the computer todivide ten by zero, it tries to do so and fails at once. If you tell the computer ... instructions that tell the computer every step to take in the proper sequence in order to solve a problem for a user. A programmeris one who writes the computer program. When the computer produces a...
... to mathematical logic, with an em-phasis on proof theory and procedures for constructing formal proofs of for- mulae algorithmically.This book is designed primarily forcomputer scientists, and ... proposition is a Hornformula iff it is a conjunction of basic Horn formulae.(a) Show that every Horn formula A is equivalent to a conjunction ofdistinct formulae of the form,Pi, or¬P1∨ ... Sets (Languages Without Equality), 1945.4.7 Completeness: Special Case of Languages Without Func-tion Symbols and Without Equality, 197PROBLEMS, 2055.5 Completeness for Languages with Function...
... such that n>0 and for all integers m>n, for every polynomial equationp(x)=0ofdegree m there are no real numbers for solutions. 11. Let p(x) stand for “x is a prime,” q(x) for “x is even,” ... −rn1 −r.Therefore by the principle of mathematical induction, our formula holds for all integers n greaterthan 0.Corollary 4.2.2 The formula for the sum of a geometric series with r =1isn−1i=0ri=1 ... dreary)proof of this formula by plugging in our earlier formula for binomial coefficients into all threeterms and verifying that we get an equality. A guiding principle of discretemathematics is thatwhen...
... of undergraduate computer science curricula and the mathematics which underpins it. Indeed, thewhole relationship between mathematics and computerscience has changed sothat mathematics is now ... rigorous way the core mathematics requirement for undergraduate computerscience students at British universitiesand polytechnics. Selections from the material could also form a one- or two-semester ... ThereforeJack is not a reasonable man.4. All gamblers are bound for ruin. No one bound for ruin is happy.Therefore no gamblers are happy.5. All computer scientists are clever or wealthy. No computer...
... LiDepartment of Mathematics andPhysics,Air Force Engineering University,Chinajianq_li@263.netWanbiao MaDepartment of Mathematics andMechanics,School of Applied Science, University of Science ... according to the ideas ofconstructing population models withdiscrete age structure and the epidemiccompartment model, we form an SIS model withdiscrete age structure asfollows:⎧⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨⎪⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩S0(t ... models with bilinear, standardor quarantine-adjusted incidence, and found that for the SIQR model with quarantine-adjusted incidence, the periodic solutions may arise by Hopf bi-furcation, but for...