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 A293891 #4 Oct 18 2017 19:01:52 %S A293891 1,11,121,992,7948,57368,407495,2762306,18558261,121903562,797628339, %T A293891 5164110575,33416303576,215354872472,1390196456927,8971242266557, %U A293891 58072455010621,376619368091666,2452238779936085,16018094650161058,105103750467074777,692390137170794830 %N A293891 Number of sets of nonempty words with a total of n letters over denary alphabet containing the tenth 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 A293891 Alois P. Heinz, <a href="/A293891/b293891.txt">Table of n, a(n) for n = 10..1000</a> %F A293891 a(n) = A293749(n) - A293748(n). %Y A293891 Column k=10 of A293113. %Y A293891 Cf. A293748, A293749. %K A293891 nonn %O A293891 10,2 %A A293891 _Alois P. Heinz_, Oct 18 2017