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 A179456 #4 Aug 04 2014 20:11:09 %S A179456 1,1,2,1,6,5,1,24,23,9,1,120,119,68,14,1,720,719,517,152,20,1,5040, %T A179456 5039,4163,1581,292,27,1,40320,40319,36180,16776,3917,508,35,1,362880, %U A179456 362879,341733,186030,52029,8489,823,44,1 %N A179456 Triangle read by rows: number of permutation trees of power n and height <= n - k. %C A179456 Partial row sums of A179454 starting from the diagonal. Special case: A179456(n,n-2) = A000096(n) for n > 1. %H A179456 Peter Luschny, <a href="http://www.oeis.org/wiki/User:Peter_Luschny/PermutationTrees"> Permutation trees</a>. %e A179456 1, %e A179456 1, %e A179456 2, 1, %e A179456 6, 5, 1, %e A179456 24, 23, 9, 1, %e A179456 120, 119, 68, 14, 1, %e A179456 720, 719, 517, 152, 20, 1, %e A179456 5040, 5039, 4163, 1581, 292, 27, 1, %e A179456 40320, 40319, 36180, 16776, 3917, 508, 35, 1, %e A179456 362880, 362879, 341733, 186030, 52029, 8489, 823, 44, 1 %Y A179456 Cf. A179454, A179455. %K A179456 nonn,tabf %O A179456 0,3 %A A179456 _Peter Luschny_, Aug 11 2010