A174913 - OEIS

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A174913

Lesser of twin primes p1 and p2 such that 2*p1+p2 is a prime number.

3, 5, 17, 29, 59, 149, 197, 227, 239, 269, 419, 569, 659, 1277, 1427, 1487, 1667, 1949, 2087, 2129, 2267, 2339, 2549, 2789, 2999, 3359, 3389, 3929, 4049, 4157, 4217, 4229, 4517, 4637, 5099, 5417, 5477, 6089, 6197, 6299, 6359, 6569, 6659, 6827, 6959, 7127

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

(p1, p2=p1+2) is a pair of twin primes.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..10000

MATHEMATICA

lst={}; Do[p1=Prime[n]; p2=p1+2; If[PrimeQ[p2]&&PrimeQ[2*p1+p2], AppendTo[lst, p1]], {n, 7!}]; lst

Transpose[Select[Partition[Prime[Range[1000]], 2, 1], #[[2]]-#[[1]] == 2 && PrimeQ[ 2#[[1]]+ #[[2]]]&]][[1]] (* Harvey P. Dale, Apr 09 2012 *)

CROSSREFS

Cf. A001359