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A074040 Product of first n twin prime pair products. 2
15, 525, 75075, 24249225, 21800053275, 38433493923825, 138322144631846175, 716923675626858725025, 7458156997546211316435075, 86984485062381462583582279725, 1656445549042930191979157352803175 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = A048599(2*n).

LINKS

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

FORMULA

a(1) = A037074(1) and a(n) = a(n-1)*A037074(n) for n>1.

EXAMPLE

The first two twin prime pairs are (3,5) and (5*7), their products: 15 and 35, therefore a(2)=15*35=525.

MATHEMATICA

a = {4, 6, 12, 18, 30, 42, 60, 72, 102, 108, 138, 150} (* A014574 *); Table[ Product[a[[k]]^2 - 1, {k, 1, n}], {n, 1, 12}]

Rest[FoldList[Times, 1, Times@@@Select[Partition[Prime[Range[50]], 2, 1], #[[2]]-#[[1]]==2&]]] (* Harvey P. Dale, Jan 19 2015 *)

CROSSREFS

Cf. A074041, A001359, A006512 & A014574.

Sequence in context: A009068 A268960 A157166 * A002403 A077206 A171197

Adjacent sequences:  A074037 A074038 A074039 * A074041 A074042 A074043

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Aug 13 2002

EXTENSIONS

Edited by Robert G. Wilson v, Aug 17 2002

STATUS

approved

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Last modified February 25 11:19 EST 2021. Contains 341606 sequences. (Running on oeis4.)