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 A378608 #10 Dec 03 2024 12:14:28
%S A378608 1,1,2,6,23,103,518,2868,17263,111925,775994,5719338,44592007,
%T A378608 366259499,3157877470,28492791496,268307662047,2630577754281,
%U A378608 26795670672626,283038010150702,3094882721541239,34977231456293519,407991690851302646,4905431774834649852,60721792897771836879
%N A378608 Number of maximal chains in the poset of all n-ary words of length <= n, ordered by B covers A iff A_i <= B_{i+k} for all i in A and some k >= 0.
%e A378608 a(3) = 6:
%e A378608 () < (1) < (1,1) < (1,1,1),
%e A378608 () < (1) < (1,1) < (1,2),
%e A378608 () < (1) < (1,1) < (2,1),
%e A378608 () < (1) < (2) < (1,2),
%e A378608 () < (1) < (2) < (2,1),
%e A378608 () < (1) < (2) < (3).
%o A378608 (Python)
%o A378608 def mchains(n,k): return # See A378588
%o A378608 def A378608_list(max_n): return mchains(max_n,max_n)
%Y A378608 Cf. A034841, A143672, A282698, A317145, A378382, main diagonal of A378588.
%K A378608 nonn
%O A378608 0,3
%A A378608 _John Tyler Rascoe_, Dec 01 2024