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 A202223 #7 Mar 30 2012 17:30:01 %S A202223 1,2,6,24,119,708,4914,38977,347808,3448482,37610495,447485376, %T A202223 5767807974,80062182733,1190713519497,18889300119942,318385578137273, %U A202223 5682173514985293,107042610409389945,2122634830121877061,44196021893249998467,964038681151139896083 %N A202223 Number of permutations avoiding the consecutive pattern 45213. %C A202223 a(n) is the number of permutations on [n] that avoid the consecutive pattern 45213. It is the same as the number of permutations which avoid 21453, 31254 or 35412. %H A202223 Ray Chandler, <a href="/A202223/b202223.txt">Table of n, a(n) for n = 1..40</a> %H A202223 A. Baxter, B. Nakamura, and D. Zeilberger. <a href="http://www.math.rutgers.edu/~zeilberg/mamarim/mamarimhtml/auto.html">Automatic generation of theorems and proofs on enumerating consecutive Wilf-classes</a> %Y A202223 Cf. A177523, A202213-A202236. %K A202223 nonn %O A202223 1,2 %A A202223 _Ray Chandler_, Dec 15 2011