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A175914
Primes p such that p+2*q is prime, where q is the prime after p.
6
3, 5, 7, 11, 13, 41, 43, 59, 89, 101, 103, 113, 127, 179, 181, 191, 193, 223, 241, 269, 277, 293, 307, 311, 313, 337, 359, 421, 431, 479, 491, 521, 599, 613, 631, 673, 773, 787, 821, 823, 863, 881, 883, 907, 911, 919, 929, 937, 953, 967, 1019, 1021, 1039, 1061, 1109, 1151, 1171
OFFSET
1,1
COMMENTS
A174915 gives lesser of twin primes in this sequence.
Values of p+2*q are in A094105. [Zak Seidov, Sep 07 2012]
EXAMPLE
3 and 5 are consecutive primes, and 3+2*5 = 13 is prime. Hence 3 is in the sequence.
59 and 61 are consecutive primes, and 59+2*61 = 181 is prime. Hence 59 is in the sequence.
MATHEMATICA
p = 3; Reap[Do[q = NextPrime[p]; If[PrimeQ[p + 2 q], Sow[p]]; p = q, {10^3}]][[2, 1]] (* Zak Seidov, Oct 14 2012 *)
PROG
(Magma) [p: p in PrimesUpTo(1200) | IsPrime(p+2*NextPrime(p))]; // Klaus Brockhaus, Dec 06 2010
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Dec 05 2010
STATUS
approved