id:A125215 - OEIS Search Results

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Semiprimes s such that s-/+2 are primes.

+0
3

9, 15, 21, 39, 69, 111, 129, 309, 381, 489, 501, 771, 879, 939, 1011, 1299, 1569, 2271, 2391, 2661, 2859, 3039, 3189, 3459, 3849, 3909, 3921, 4449, 4791, 4971, 5001, 5079, 5169, 5349, 5739, 6009, 6999, 7041, 7671, 8691, 8781, 9201, 10599, 11469, 11829 (list; graph; listen)

	OFFSET	`1,1`
	MATHEMATICA	`Reap[Do[p=Prime[i]; If[PrimeQ[p+4]&&Total[Last/@FactorInteger[p+2]]==2, Sow[p+2]], {i, 2*10^3}]][[2, 1]]`
	CROSSREFS	`Sequence in context: A072569 A072572 A029708 this_sequence A102739 A124622 A075638` `Adjacent sequences: A125212 A125213 A125214 this_sequence A125216 A125217 A125218`
	KEYWORD	`nonn`
	AUTHOR	`Zak Seidov (zakseidov(AT)yahoo.com), Nov 24 2006`

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Last modified December 16 17:18 EST 2009. Contains 170825 sequences.

AT&T Labs Research