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%I #11 Nov 26 2021 06:38:51
%S 1,15,504,17280,1108800,59304960,5613753600,944393748480,
%T 83547459072000,18057977118720000,2985679725841612800,
%U 366843845931171840000,71218197373471948800000,22048551163610844364800000,7384118713322835982417920000
%N a(n) = v(n+1)/(8*v(n)), where v=A203524.
%C See A093883 for a discussion and guide to related sequences.
%t f[j_] := Prime[j + 1]; z = 17;
%t v[n_] := Product[Product[f[k] + f[j], {j, 1, k - 1}], {k, 2, n}]
%t d[n_] := Product[(i - 1)!, {i, 1, n}] (* A000178 *)
%t Table[v[n], {n, 1, z}] (* A203524 *)
%t Table[v[n + 1]/(8 v[n]), {n, 1, z - 1}] (* A203525 *)
%t Table[v[n]/d[n], {n, 1, 20}] (* A203526 *)
%Y Cf. A000040, A093883, A203315, A203524, A203526.
%K nonn,easy
%O 1,2
%A _Clark Kimberling_, Jan 03 2012
%E Definition corrected by _Georg Fischer_, Nov 26 2021