Peter Taylor
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 Oct 15 answered Number of unlabeled simple graphs with $n$ nodes even for all $n\ge 5$? Oct 15 comment Number of unlabeled simple graphs with $n$ nodes even for all $n\ge 5$? Ah, it doesn't have simple in the title so my search didn't find it. Thanks for adding the link. Oct 15 comment Number of unlabeled simple graphs with $n$ nodes even for all $n\ge 5$? Are you referring to A005470 (in which case you seem to be missing the very important word planar from the question) or to a different sequence? Oct 12 reviewed Approve Limit of a sum is the sum of the limits: proof by induction Oct 12 reviewed Close Can anyone help me prove block diagonal matrix? Oct 12 reviewed Close Simple Question on Quantifier Logic Oct 12 reviewed Close Growth of $\sum_{x=1}^{n-1} \left\lceil n-\sqrt{n^{2}-x^{2} } \right\rceil$ Oct 12 revised Counting all possible board positions in Quoridor added 1987 characters in body Oct 12 comment Counting all possible board positions in Quoridor @lameK, I got 55 by writing a short computer program, but as I used an obscure language to do it I didn't see any benefit to sharing it. I'll add some examples to the last paragraph. Oct 10 revised Counting all possible board positions in Quoridor added 152 characters in body Oct 10 answered Counting all possible board positions in Quoridor Oct 6 reviewed Close Integrating by splitting up trig functions Oct 6 comment Can anyone extend my findings for Langford Pairings? I don't actually see a question. If this is an attempt to follow David Eppstein's advice that for your ideas to be included in the Wikipedia page on Langford pairing you should first get them published, then you should be aware that he was talking about publication in a peer-reviewed journal, not on a Q&A site. Oct 6 answered How to prove 2 is a primitive root mod 37, without calculating all powers of 2 mod 37? Sep 30 awarded Explainer Sep 22 comment No simple closed form for Bell numbers The premise of your question is somewhat unclear, because "closed form" is a somewhat variable quantity. Unless you allow factorials in a closed form, I can't think of any basic combinatorial quantity which has one. Allowing them lets in binomial coefficients and therefore Catalan numbers, but what else? Such basic combinatorial quantities as Stirling numbers and the partition function don't have well-known closed forms. Sep 13 reviewed Reopen condition for transitivity Sep 12 revised Partial sums of Nicomachus' Triangle rows produce Stirling numbers of the 2nd kind? added 1110 characters in body Sep 12 answered Partial sums of Nicomachus' Triangle rows produce Stirling numbers of the 2nd kind? Sep 11 revised 4-part partitions of n and 3n deleted 90 characters in body; edited tags; edited title