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A203532 v(n+1)/v(n), where v=A203530. 3
10, 168, 3315, 76608, 2661120, 113667840, 4311354600, 178738560000, 11178747740160, 791853627801600, 44783640216315000, 2693449157020876800, 246209683227475968000, 17126298576096297588000, 1253392853589570355200000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..15.

MATHEMATICA

t = Table[If[PrimeQ[k], 0, k], {k, 1, 100}];

composite = Rest[Rest[Union[t]]]       (* A002808 *)

f[j_] := composite[[j]]; z = 20;

v[n_] := Product[Product[f[k] + f[j], {j, 1, k - 1}], {k, 2, n}]

d[n_] := Product[(i - 1)!, {i, 1, n}]  (* A000178 *)

Table[v[n], {n, 1, z}]                 (* A203530 *)

Table[v[n + 1]/v[n], {n, 1, z - 1}]    (* A203532 *)

Table[v[n]/d[n], {n, 1, 20}]           (* A203533 *)

CROSSREFS

Cf. A203530, A203532, A002808, A093883, A203419.

Sequence in context: A006297 A279292 A099711 * A325911 A246501 A120977

Adjacent sequences:  A203529 A203530 A203531 * A203533 A203534 A203535

KEYWORD

nonn

AUTHOR

Clark Kimberling, Jan 03 2012

STATUS

approved

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Last modified May 25 11:07 EDT 2020. Contains 334592 sequences. (Running on oeis4.)