#ATTENDANCE QUIZ FOR LECTURE 18 of Dr. Z.'s Math454(02) Rutgers University

# Please Edit this .txt page with Answers

#Email  ShaloshBEkhad@gmail.com 
#Subject: p18
#with an attachment called
#p18FirstLast.txt
#(e.g. p18DoronZeilberger.txt)

#Right after finishing watching the lecture but no later than Nov. 10, 2020, 8:00pm


THE NUMBER OF ATTENDANCE QUESTIONS WERE: 8

PLEASE LIST ALL THE QUESTIONS FOLLOWED, AFTER EACH, BY THE ANSWER

Question 1:
Who invented latin squares and latin greco squares, and what are they?
Leonard Euler invented latin squares
Answer 1:
In combinatorics and in experimental design, a Latin square is an n × n array filled with n different symbols, each occurring exactly once in each row and exactly once in each column

Question 2:
What is nops(AllGraphs(20))

Answer 2:
1569275433846670190958947355801916604025588861116008628224

Question 3:
What is CC(G, 38)

Answer 3:



Question 4:
Is this sequence in the OEIS? If it is what is its A number

Answer 4:
A001187		Number of connected labeled graphs with n nodes.

Question 5:
Draw the graph manually

Answer 5:
8-1-4-6-9-3-5-10-5-7-2

Question 6:
i) What is the sequence in the OEIS
ii) What is the A number
iii) What is the number of (labeled) trees with 20 vertices

Answer 6:
Yes it is
A000272		Number of trees on n labeled nodes: n^(n-2) with a(0)=1
a(20) = 262144000000000000000000

Question 7
Is this in the OEIS? What is the A number, reason?

Answer 7:

A057500		Number of connected labeled graphs with n edges and n nodes.

Question 8
Is this in the OEIS? A number?

Answer 8:
A061540		Number of connected labeled graphs with n nodes and n+1 edges.