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A079390 spf(n) * spf(n+1) * spf(n+2), where spf=A020639 (smallest prime factor). 1
6, 12, 30, 20, 70, 28, 42, 12, 66, 44, 286, 52, 78, 12, 102, 68, 646, 76, 114, 12, 138, 92, 230, 20, 30, 12, 174, 116, 1798, 124, 186, 12, 30, 20, 370, 148, 222, 12, 246, 164, 3526, 172, 258, 12, 282, 188, 658, 28, 42, 12, 318, 212, 530, 20, 30, 12, 354, 236, 7198, 244 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For n>2, a(n) is a record value iff (n,n+2) is a twin prime pair (conjecture).

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

Times@@@Partition[Table[FactorInteger[n][[1, 1]], {n, 70}], 3, 1] (* Harvey P. Dale, Oct 06 2015 *)

CROSSREFS

Cf. A001359, A006512, A014574.

Sequence in context: A109510 A034715 A294730 * A124679 A242949 A143272

Adjacent sequences:  A079387 A079388 A079389 * A079391 A079392 A079393

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Feb 20 2003

STATUS

approved

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Last modified December 13 10:42 EST 2018. Contains 318086 sequences. (Running on oeis4.)