A243410 Primes p such that 1000p-1, 1000p-3, 1000p-7 and 1000p-9 are all prime.

10193, 13217, 34457, 36767, 57773, 76631, 103043, 157823, 191033, 194813, 212243, 229799, 242273, 242867, 249377, 256889, 261563, 264071, 361511, 457871, 486293, 502841, 508517, 647837, 653621, 694409, 697511, 777437, 798143, 825611, 847031

Offset

1,1

Comments

Primes in A064977.

Links

Table of n, a(n) for n=1..31.

Example

10193 is prime and 1000*10193-1 = 10192999 is prime, 1000*10193-3 = 10192997 is prime, 1000*10193-7 = 10192993 is prime and 1000*10193-9 = 10192991 is prime. Thus 10193 is a member of this sequence.

Prog

(Python)
import sympy
from sympy import isprime
from sympy import prime
{print(prime(n), end=', ') 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)}
(PARI) for(n=1, 10^5, if(ispseudoprime(1000*prime(n)-1) && ispseudoprime(1000*prime(n)-3) && ispseudoprime(1000*prime(n)-7) && ispseudoprime(1000*prime(n)-9), print1(prime(n), ", ")))

Crossrefs

Cf. A242562, A064977.

Sequence in context: A050267 A102326 A216262 * A221119 A105582 A243819

Adjacent sequences: A243407 A243408 A243409 * A243411 A243412 A243413

Keyword

nonn,less

Author

Derek Orr, Jun 04 2014

Status

approved