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 A158434 #14 Feb 16 2025 08:33:09
%S A158434 1,26,460,7068,102676,1466870,21055493,307660035,4616675543,
%T A158434 71598646435,1153132523804
%N A158434 Number of permutations of 1..n containing the relative rank sequence { 51342 } at any spacing.
%C A158434 Same series for 25341, 41325, 14352, 52314, 24315, 42351, 15324.
%H A158434 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PermutationPattern.html">Permutation Pattern</a>
%F A158434 a(n) = n! - A256200(n). - _Alois P. Heinz_, May 19 2020
%Y A158434 Cf. A000142, A056986, A158005, A256200.
%K A158434 nonn,more
%O A158434 5,2
%A A158434 _R. H. Hardin_, Mar 18 2009