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.
%I A217321 #7 Oct 14 2012 17:47:00 %S A217321 1,9,89,639,4655,30330,198148,1233743,7694099,46938514,287070944, %T A217321 1738940782,10570927022,64059763010,389873574058,2373799261605, %U A217321 14522526860316,89060416668016,548932942208392,3395326330414774,21109553761623110,131785019270029876 %N A217321 Number of self-inverse permutations in S_n with longest increasing subsequence of length 9. %C A217321 Also the number of Young tableaux with n cells and 9 rows. %H A217321 Alois P. Heinz, <a href="/A217321/b217321.txt">Table of n, a(n) for n = 9..350</a> %F A217321 a(n) = A182172(n,9)-A182172(n,8) = A212915(n)-A007580(n). %Y A217321 Column k=9 of A047884. %Y A217321 Cf. A007580, A182172, A212915. %K A217321 nonn %O A217321 9,2 %A A217321 _Alois P. Heinz_, Sep 30 2012