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 A238987 #25 Mar 14 2014 16:00:02 %S A238987 0,0,0,1,10,75,522,3579,24670,172198,1219974,8776255,64082132, %T A238987 474605417,3562460562,27079243352,208281537572 %N A238987 Number of permutations of length n containing exactly 1 occurrence of the pattern 1324. %D A238987 B. K. Nakamura, Computational methods in permutation patterns, PhD Dissertation, Rutgers University, May 2013. %H A238987 Fredrik Johansson, Brian Nakamura, <a href="http://arxiv.org/abs/1309.7117">Using functional equations to enumerate 1324-avoiding permutations</a>, arXiv:1309.7117 [math.CO], (2013). %e A238987 a(4)=1 since 1324 is the only length 4 permutation with 1 occurrence of the pattern 1324. %p A238987 # Program can be obtained from authors' personal websites. %K A238987 nonn,more %O A238987 1,5 %A A238987 _Brian Nakamura_, Mar 12 2014