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A203528 a(n) = v(n+1)/v(n), where v=A203527.

%I A203528 #11 Nov 26 2021 06:39:05
%S A203528 5,70,1512,33150,842688,34594560,1705017600,68981673600,3038555520000,
%T A203528 212396207063040,16628926183833600,985240084758930000,
%U A203528 61949330611480166400,6155242080686899200000,445283762978503737288000
%N A203528 a(n) = v(n+1)/v(n), where v=A203527.
%C A203528 See A093883 for a discussion and guide to related sequences.
%t A203528 t = Table[If[PrimeQ[k], 0, k], {k, 1, 100}];
%t A203528 nonprime = Rest[Union[t]]              (* A018252 *)
%t A203528 f[j_] := nonprime[[j]]; z = 20;
%t A203528 v[n_] := Product[Product[f[k] + f[j], {j, 1, k - 1}], {k, 2, n}]
%t A203528 d[n_] := Product[(i - 1)!, {i, 1, n}]  (* A000178 *)
%t A203528 Table[v[n], {n, 1, z}]                 (* A203527 *)
%t A203528 Table[v[n + 1]/v[n], {n, 1, z - 1}]    (* A203528 *)
%t A203528 Table[v[n]/d[n], {n, 1, 20}]           (* A203529 *)
%Y A203528 Cf. A203527, A203529, A018252, A093883, A203416.
%K A203528 nonn,easy
%O A203528 1,1
%A A203528 _Clark Kimberling_, Jan 03 2012
%E A203528 Definition corrected by _Georg Fischer_, Nov 26 2021