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A242562
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Primes p such that 1000p+1, 1000p+3, 1000p+7 and 1000p+9 are prime.
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2
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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
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OFFSET
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1,1
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LINKS
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EXAMPLE
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130001, 130003, 130007 and 130009 are all prime. Thus 13 is a member of this sequence.
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PROG
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(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)}
(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)));
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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