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 A224294 #5 Apr 03 2013 11:57:24 %S A224294 0,0,0,0,0,2,34,382,3518,28708,216098,1536960,10488708,69393216, %T A224294 448301130,2842611306,17758399872,109613418746,669950441982, %U A224294 4061411038376,24453911859134,146393798673526,872121958672162,5173931524573894,30584965562156650 %N A224294 Number of permutations of length n containing exactly 2 occurrences of 1234 and 2 occurrences of 1243. %H A224294 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 A224294 # Programs can be obtained from author's personal website. %Y A224294 Cf. A006318, A224292, A224293. %K A224294 nonn %O A224294 1,6 %A A224294 _Brian Nakamura_, Apr 03 2013