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A243410 Primes p such that 1000p-1, 1000p-3, 1000p-7 and 1000p-9 are all prime. 0
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified July 20 11:28 EDT 2019. Contains 325180 sequences. (Running on oeis4.)