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 A224296 #5 Apr 03 2013 11:58:38 %S A224296 0,0,0,0,1,18,219,2294,22457,212994,1992364,18553588,172889838, %T A224296 1616683912,15193902185,143632773054,1366274116893,13078787860290, %U A224296 125984999505040,1221032658065388,11904323953163434,116721427446951748,1150690705785803998 %N A224296 Number of permutations of length n avoiding 12345 and containing exactly 1 occurrence of 12354. %C A224296 a(n) is also the number of permutations of length n avoiding 12354 and containing exactly 1 occurrence of 12345. %H A224296 B. Nakamura, <a href="http://arxiv.org/abs/1301.5080">Approaches for enumerating permutations with a prescribed number of occurrences of patterns</a>, arXiv 1301.5080, 2013. %p A224296 # Programs can be obtained from author's personal website. %Y A224296 Cf. A224295. %K A224296 nonn %O A224296 1,6 %A A224296 _Brian Nakamura_, Apr 03 2013