A271982 Primes p such that p + 42 is also prime.

5, 11, 17, 19, 29, 31, 37, 41, 47, 59, 61, 67, 71, 89, 97, 107, 109, 131, 137, 139, 149, 151, 157, 181, 191, 197, 199, 227, 229, 239, 241, 251, 269, 271, 307, 311, 317, 331, 337, 347, 359, 367, 379, 389, 397, 401, 419, 421, 449, 457, 461

Offset: 1

Author

Karl V. Keller, Jr., Apr 17 2016

Keywords

• nonn

Comments

A134120 is a subsequence of this sequence.

Examples

			5 is a term because 5 + 42 = 47 is also prime.
11 is a term because 11 + 42 = 53 is also prime.
		

Links

• Karl V. Keller, Jr., Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000040, A134120.

Programs

Maple

A271982:=n->`if`(isprime(n) and isprime(n+42), n, NULL): seq(A271982(n), n=1..10^3); # Wesley Ivan Hurt, Feb 12 2017

Mathematica

Select[Prime@ Range@ 90, PrimeQ[# + 42] &] (* Michael De Vlieger, Apr 18 2016 *)

PARI

lista(nn) = forprime(p=2, nn, if (isprime(p+42), print1(p, ", "))); \\ Michel Marcus, Apr 19 2016

Python

from sympy import isprime
for i in range(3,2001,2):
    if isprime(i) and isprime(i+42): print (i,end=', ')