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 A213875 #5 Jun 24 2012 12:58:39 %S A213875 1,120,945,87595,19558470,7236515981,3745777177366,2468722942369153, %T A213875 1953740543358042205,1785201362960729511070,1831976833971352074708780, %U A213875 2068976591723429552651743620,2532392303303120865350779766160,3319547855302819899374947284511390 %N A213875 Number of words w where each letter of the 5-ary alphabet occurs n times and for every prefix z of w we have #(z,a_i) = 0 or #(z,a_i) >= #(z,a_j) for all j>i and #(z,a_i) counts the occurrences of the i-th letter in z. %H A213875 Alois P. Heinz, <a href="/A213875/b213875.txt">Table of n, a(n) for n = 0..50</a> %e A213875 a(0) = 1: the empty word. %e A213875 a(1) = 120: abcde, abced, abdce, ..., edbca, edcab, edcba, (all permutations of 5 letters). %e A213875 a(2) = 945: aabbccddee, aabbccdede, aabbccedde, ..., edcaabbcde, edcababcde, edcbaabcde. %Y A213875 Column k=5 of A213275. %K A213875 nonn %O A213875 0,2 %A A213875 _Alois P. Heinz_, Jun 23 2012