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 A225964 #9 Aug 05 2015 16:53:35 %S A225964 1,9,63,419,2868,20932,165662,1432746,13578086,140951642,1598792812, %T A225964 19739303596,264041415799,3807692229035,58907522237037, %U A225964 973166134330293,17094936849558000,318092941562300736,6248389843759774380,129180041710223480596,2803277432655658573548 %N A225964 Number of permutations of [n] having exactly 3 strong fixed blocks. %C A225964 See A186373 for the definition of strong fixed blocks. %H A225964 Alois P. Heinz, <a href="/A225964/b225964.txt">Table of n, a(n) for n = 7..450</a> %F A225964 a(n) ~ 2 * n! / n^5. - _Vaclav Kotesovec_, Aug 29 2014 %Y A225964 Column k=3 of A186373. %K A225964 nonn %O A225964 7,2 %A A225964 _Alois P. Heinz_, May 22 2013