cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A008327 Triangle read by rows: T(n,k) is the number of simple regular bipartite graphs with 2n nodes and degree k, (0 <= k <= n).

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%I A008327 #20 Apr 04 2020 14:39:43
%S A008327 1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,2,2,1,1,1,1,4,6,4,1,1,1,1,4,14,14,
%T A008327 4,1,1,1,1,7,41,130,41,7,1,1,1,1,8,157,1981,1981,157,8,1,1,1,1,12,725,
%U A008327 62616,304496,62616,725,12,1,1,1,1,14,4196,2806508,78322916
%N A008327 Triangle read by rows: T(n,k) is the number of simple regular bipartite graphs with 2n nodes and degree k, (0 <= k <= n).
%C A008327 This sequence can be derived from A008326 by Euler transform. - _Andrew Howroyd_, Apr 03 2020
%H A008327 Andrew Howroyd, <a href="/A008327/b008327.txt">Table of n, a(n) for n = 0..189</a>
%H A008327 B. D. McKay and E. Rogoyski, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v2i1n3">Latin squares of order ten</a>, Electron. J. Combinatorics, 2 (1995) #N3.
%F A008327 Column k is the Euler transform of column k of A008326. - _Andrew Howroyd_, Apr 03 2020
%e A008327 Triangle begins:
%e A008327   1,
%e A008327   1, 1,
%e A008327   1, 1, 1,
%e A008327   1, 1, 1,   1,
%e A008327   1, 1, 2,   1,    1,
%e A008327   1, 1, 2,   2,    1,    1,
%e A008327   1, 1, 4,   6,    4,    1,   1;
%e A008327   1, 1, 4,  14,   14,    4,   1, 1;
%e A008327   1, 1, 7,  41,  130,   41,   7, 1, 1;
%e A008327   1, 1, 8, 157, 1981, 1981, 157, 8, 1, 1;
%e A008327   ...
%Y A008327 Column k=0..5 are A000012, A000012, A002865, A008325, A333730, A333731.
%Y A008327 Row sums are A008324.
%Y A008327 Cf. A051031, A008326, A087114, A133687, A333159.
%K A008327 nonn,tabl,nice
%O A008327 0,13
%A A008327 _Brendan McKay_
%E A008327 More terms from Eric Rogoyski, May 15 1997
%E A008327 Name clarified by _Andrew Howroyd_, Sep 05 2018