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A203307 v(n+1)/(2*v(n)), where v=A203305. 4
1, 12, 672, 161280, 159989760, 645078712320, 10486399547473920, 684552162459097497600, 179100751368498596492083200, 187617350297573441752474740326400, 786539962489104046627462744981792358400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..11.

FORMULA

a(n)=(1/2)A028365(n) for n>0.

MATHEMATICA

f[j_] := 2^j - 1; z = 15;

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

Table[v[n], {n, 1, z}]  (* A203305 *)

Table[v[n + 1]/v[n], {n, 1, z - 1}]  (* A028365 *)

%/2  (* A203307 *)

CROSSREFS

Cf. A203305, A028365.

Sequence in context: A295870 A177322 A060612 * A171105 A215686 A277691

Adjacent sequences:  A203304 A203305 A203306 * A203308 A203309 A203310

KEYWORD

nonn

AUTHOR

Clark Kimberling, Jan 01 2012

STATUS

approved

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Last modified October 1 04:06 EDT 2020. Contains 337441 sequences. (Running on oeis4.)