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 A347845 #15 Jun 27 2025 09:34:26
%S A347845 1,1,10,804,518376,2674194448,110368339035808,36440751353074277952,
%T A347845 96254339565438079064819328,2033964285682509941820879401890048,
%U A347845 343839935881726495233403720783311789640192,465006794599984581603302662503095770372066384585728
%N A347845 a(n) is the number of (strict) chains of subspaces with ends 0 and (F_8)^n.
%H A347845 Alois P. Heinz, <a href="/A347845/b347845.txt">Table of n, a(n) for n = 0..47</a> (terms n = 1..40 from Álvar Ibeas)
%F A347845 a(n) = Sum_{L partition of n} A347490(n, L) * A036038(len(L), sig(L)), where sig(L) is the partition composed by the part multiplicities of L.
%e A347845 a(3) = 804 = 1 * 1 + 73 * 2 + 657 * 1, counting:
%e A347845 the unrefined chain 0 < (F_8)^3;
%e A347845 73 chains 0 < V < (F_8)^3, with dim(V) = 1; another
%e A347845 73 chains 0 < V < (F_8)^3, with dim(V) = 2; and
%e A347845 657 chains 0 < V_1 < V_2 < (F_8)^3.
%Y A347845 Cf. A289545, A347490, A036038.
%Y A347845 Column k=8 of A381426.
%K A347845 nonn
%O A347845 0,3
%A A347845 _Álvar Ibeas_, Sep 15 2021
%E A347845 a(0)=1 prepended by _Alois P. Heinz_, Jun 25 2025