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Primes q such that 10*q-3 and 10*q+1 are cousin primes.
2

%I #18 Mar 18 2021 05:55:23

%S 7,13,31,97,109,157,271,523,601,691,769,829,1063,1069,1201,1249,1291,

%T 1483,1489,1567,1579,1609,1693,1747,1831,2203,2281,2383,2803,2887,

%U 2953,3511,3967,4513,4651,5023,5059,5437,5653,5779,5821,6151,6163,6199,6361,6367

%N Primes q such that 10*q-3 and 10*q+1 are cousin primes.

%C A pair of cousin primes are primes of the form p and p+4 (where p+2 may or may not be a prime).

%C Generates cousin primes such that the last digits of the primes are 7 and 1 in base 10.

%o (PARI) isok(p) = isprime(p) && isprime(10*p-3) && isprime(10*p+1); \\ _Michel Marcus_, Mar 05 2021

%Y Cf. A046132, A342183, A342185.

%K nonn

%O 1,1

%A _Tamas Nagy_, Mar 04 2021