#ATTENDANCE QUIZ FOR LECTURE 19 of Dr. Z.'s Math454(02) Rutgers University # Please Edit this .txt page with Answers #Email ShaloshBEkhad@gmail.com #Subject: p19 #with an attachment called #p19FirstLast.txt #(e.g. p19DoronZeilberger.txt) #Right after finishing watching the lecture but no later than Nov. 13, 2020, 8:00pm THE NUMBER OF ATTENDANCE QUESTIONS WERE: 8 PLEASE LIST ALL THE QUESTIONS FOLLOWED, AFTER EACH, BY THE ANSWER Question 1 i)WHat is the explicitly expression for the sequence a(0) a(1) = 0, a(2) = 0 a(3) = 1 ... ii) Use maple to find an explicit expression for the generating function a(n) = n^3 iii) Basically the binomial theorem Answer 1 i) -x^3/(-1 + x) ii) x*(x^2 + 4*x + 1)/(-1 + x)^4 iii) (1 + x)^n Question 2 Find the egf of a(n) = n for 0<=n<=5, a(n) if n>=6 Answer 2 x + x^2 + 1/2*x^3 + 1/6*x^4 + 1/24*x^5 Question 3 Whatis the EGF of a(n) for n =0,1,2,3,4,5 and a(n) = 1 for n>=6 Answer 3 exp(x) - x^5/120 - x^4/24 - x^3/6 - x^2/2 - x - 1 Question 4 Find the egf of a(0) = 0 a(n) = n-2! for n>=2 Answer 4 -x*ln(1 - x) + ln(1 - x) + x Question 5 i) What is the OEIS A number of this question ii) How many digits does the number of labeled connected graphs with 150 vertices has Answer 5 i) A001187 ii) 3365 Question 6 Use the technique of weight enumeration to find the exact number of sequences a[1], a[2], a[3], a[4] ... a[r] (r can be any length) where each of the a[i] is a member of {3, 4, 7} that add up to 1001 Question 6 37327228629056835260060479719213438237141848693395064396004356099234232222305300761357555310103620202925186169 Question 7 Is [{{1, 3, 4}, {6, 7}}, 52] a member of X(7)\ Answer 7 Yes it is since 3+2+2 = 7 Question 8 How many triples of the form [labeled tree, permutation, set partition] Answer 8