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Primes p such that 1000p-1, 1000p-3, 1000p-7 and 1000p-9 are all prime.
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%I #8 Jun 06 2014 14:45:15

%S 10193,13217,34457,36767,57773,76631,103043,157823,191033,194813,

%T 212243,229799,242273,242867,249377,256889,261563,264071,361511,

%U 457871,486293,502841,508517,647837,653621,694409,697511,777437,798143,825611,847031

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

%C Primes in A064977.

%e 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.

%o (Python)

%o import sympy

%o from sympy import isprime

%o from sympy import prime

%o {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)}

%o (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),", ")))

%Y Cf. A242562, A064977.

%K nonn,less

%O 1,1

%A _Derek Orr_, Jun 04 2014