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 A241785 #3 Apr 28 2014 12:05:46 %S A241785 1,1,2,9,49,322,2411,19868,178832,1724689,17728545,192634930, %T A241785 2201760840,26341552085,328644606302,4261866683006,57288746422850, %U A241785 796337785825197,11422744246417607,168765251734898485,2564015637845130072,39998356172536082076,639840751503820832346 %N A241785 Number of standard Young tableaux with 2n cells and exactly n successions. %C A241785 A succession is a pair of cells (v, v+1) lying in the same row. %C A241785 Also number of ballot sequences of length 2n having exactly n flat steps. %F A241785 a(n) = A238125(2n,n). %K A241785 nonn %O A241785 0,3 %A A241785 _Joerg Arndt_ and _Alois P. Heinz_, Apr 28 2014