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A254462
Primes prime(n) such that prime(n) + 5*n is also prime.
4
2, 3, 13, 19, 29, 37, 43, 61, 113, 151, 163, 173, 223, 229, 239, 251, 311, 317, 337, 359, 373, 397, 409, 433, 503, 601, 647, 659, 673, 683, 757, 821, 857, 863, 887, 941, 1061, 1097, 1109, 1123, 1213, 1249, 1291, 1307, 1373, 1423, 1439, 1493, 1511, 1531, 1559
OFFSET
1,1
LINKS
EXAMPLE
prime(2)=3 is in the sequence because 3+5*2 = 13 is prime.
prime(6)=13 is in the sequence because 13+5*6 = 43 is prime.
MAPLE
P:= select(isprime, [2, seq(i, i=3..10000, 2)]):
P[select(i -> isprime(P[i]+5*i), [$1..nops(P)])]; # Robert Israel, Aug 01 2024
MATHEMATICA
Prime[Select[Range[300], PrimeQ[Prime[#] + 5 #] &]]
PROG
(Magma) [NthPrime(n): n in [1..300] | IsPrime(NthPrime(n)+5*n)];
CROSSREFS
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Feb 04 2015
STATUS
approved