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A154667
Averages of twin prime pairs such that p1 * p2 + AverageTwinPrime is prime.
2
4, 6, 30, 60, 138, 180, 240, 420, 618, 1050, 1608, 1698, 1788, 2268, 2310, 2730, 3258, 3390, 3528, 3768, 4158, 4218, 4338, 4800, 5640, 5868, 6660, 6690, 6870, 6960, 7488, 7548, 7590, 8538, 8628, 8970, 9630, 9858, 9930, 10458, 11118, 11970, 12540, 13338
OFFSET
1,1
LINKS
EXAMPLE
3*5 + 4 = 19.
5*7 + 6 = 41.
MATHEMATICA
lst={}; Do[If[PrimeQ[n-1]&&PrimeQ[n+1], If[PrimeQ[(n-1)*(n+1)+n], AppendTo[lst, n]]], {n, 8!}]; lst
PROG
(Magma) [p+1:p in PrimesUpTo(14000)|IsPrime(p+2) and IsPrime(p*(p+2)+p+1)]; // Marius A. Burtea, Dec 21 2019
CROSSREFS
Cf. A154666.
A014574 INTERSECT A045546. - R. J. Mathar, May 31 2010
Sequence in context: A056221 A046849 A090530 * A376482 A093121 A248048
KEYWORD
nonn
AUTHOR
STATUS
approved