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6:22 AM
@Simd The answer is pretty clear if you think about it. It is left as an exercise for you, dear reader. :)
6:55 AM
@Simd so if i understand it correctly, if i take a graph and swap the labels for any two vertices, the new graph and the original graph are isomorphic
7:23 AM
@zoomlogo yes
2 hours later…
9:12 AM
@DLosc 😁
9:44 AM
@Simd well for a start there are several graphs with no cycles, but there's also one with only a 5-cycle and one with only a 4-cycle
@Neil ok... sounds like progress
2 hours later…
11:50 AM
actually there's one with three 4-cycles
12:13 PM
Q: Egyptian fraction representations of 1 without prime denominators

Max MullerBackground As noted in this question, for all positive integers \$n>2\$ there exists at least one Egyptian fraction representation (EFR) of \$n\$ distinct positive integers \$a_{1} < a_{2} < \dots < a_{n}\$ such that $$ \sum_{k=1}^{n} \frac{1}{a_{k}} = 1. \tag{1} \label{1} $$ When \$n=3\$, for in...

5 hours later…
5:15 PM
Q: People who know the secret?

VaibhavI was trying to solve a problem which says to count the number of people who know the secret (given total number of people who will be attending meetings) initally peroson 0 only knows the secret and he tells the secret to some person named at time 0. a vector has been given to us which contains ...

5:54 PM
@NewPosts 1 more close vote needed, i think
how many close votes are needed to close as off topic? 4 or 5?
6:15 PM
A: Sandbox for Proposed Challenges

TbwIntroduction Tensor contraction is an operation that can be performed on a tensor. It is a generalization of the idea of the trace of a matrix. For example, if we have a rank-2 tensor (a matrix) and we contract along both of its axes, we take the sum of each entry in which the indices of these ax...

6:59 PM
Q: Search the deepest depths of an array

Alan BreadelGiven a ragged array, find the length of the largest subarray that contains the depth of that subarray. The base array layer has a depth of 0. Here is an example: [1, 2, [3, 4, [2, 5]], 0] Here, the subarray [2, 5] contains its own depth 2 and has a length of 2 as well. But in the outermost suba...

7:12 PM
@Neil hmm

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