A175914 Primes p such that p+2*q is prime, where q is the prime after p.
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
Keywords
Examples
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.
Links
- Zak Seidov, Table of n, a(n) for n = 1..1000
Programs
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Magma
[p: p in PrimesUpTo(1200) | IsPrime(p+2*NextPrime(p))]; // Klaus Brockhaus, Dec 06 2010
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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 *)
Comments