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 A293885 #4 Oct 18 2017 19:16:59 %S A293885 1,5,25,102,410,1545,5784,21015,76248,272377,974208,3455177,12287351, %T A293885 43502174,154554897,547955950,1950335934,6937352521,24777223885, %U A293885 88515560121,317513893877,1139848959317,4108296484542,14823490668322,53689879422115,194704264528116 %N A293885 Number of sets of nonempty words with a total of n letters over quaternary alphabet containing the fourth letter such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter. %H A293885 Alois P. Heinz, <a href="/A293885/b293885.txt">Table of n, a(n) for n = 4..1000</a> %F A293885 a(n) = A293743(n) - A293742(n). %Y A293885 Column k=4 of A293113. %Y A293885 Cf. A293742, A293743. %K A293885 nonn %O A293885 4,2 %A A293885 _Alois P. Heinz_, Oct 18 2017