A242562 Primes p such that 1000p+1, 1000p+3, 1000p+7 and 1000p+9 are prime.

13, 1447, 5527, 28201, 36217, 75079, 81157, 95911, 187423, 188677, 202327, 210643, 248077, 263323, 282589, 283267, 423043, 466897, 472597, 478189, 478603, 631273, 640261, 695749, 730111, 736279, 806929, 808021, 917641, 964303, 1018177, 1026547, 1064263, 1108489, 1150861

Offset: 1

Author

Derek Orr, May 17 2014

Keywords

• nonn

Examples

			130001, 130003, 130007 and 130009 are all prime. Thus 13 is a member of this sequence.
		

Crossrefs

Cf. A236042, A067267.

Programs

PARI

for(n=1,10^5,s=prime(n);if(ispseudoprime(1000*s+1) && ispseudoprime(1000*s+3) && ispseudoprime(1000*s+7) && ispseudoprime(1000*s+9),print(s)));

Python

import sympy
from sympy import isprime
from sympy import prime
{print(prime(n)) for n in range(1,10**5) if isprime(1000*prime(n)+1) and isprime(1000*prime(n)+3) and isprime(1000*prime(n)+7) and isprime(1000*prime(n)+9)}