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 A343793 #7 Apr 29 2021 20:27:10
%S A343793 1,1,3,13,75,541,4683,47293,545835,7087261,102247562,1622632551,
%T A343793 28091567067,526858335797,10641342662135,230283183134017,
%U A343793 5315654473869451,130370761261559229,3385534496252337939,92801582269262225397,2677687636903407184463,81124819758167172293305
%N A343793 Number of ordered partitions of an n-set without blocks of size 10.
%F A343793 E.g.f.: 1 / (2 + x^10/10! - exp(x)).
%p A343793 a:= proc(n) option remember; `if`(n=0, 1, add(
%p A343793 `if`(j=10, 0, a(n-j)*binomial(n, j)), j=1..n))
%p A343793 end:
%p A343793 seq(a(n), n=0..21); # _Alois P. Heinz_, Apr 29 2021
%t A343793 nmax = 21; CoefficientList[Series[1/(2 + x^10/10! - Exp[x]), {x, 0, nmax}], x] Range[0, nmax]!
%t A343793 a[n_] := a[n] = If[n == 0, 1, Sum[If[k == 10, 0, Binomial[n, k] a[n - k]], {k, 1, n}]]; Table[a[n], {n, 0, 21}]
%Y A343793 Cf. A000670, A032032, A337058, A337059, A343671, A343787, A343788, A343789, A343790, A343791, A343792.
%K A343793 nonn
%O A343793 0,3
%A A343793 _Ilya Gutkovskiy_, Apr 29 2021