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

%I #17 Mar 18 2021 05:56:07

%S 2,11,23,101,149,227,239,269,353,479,557,569,647,683,809,827,983,1289,

%T 1607,1619,1823,1901,1907,2039,2213,2411,2447,2843,2879,2957,2963,

%U 3011,3119,3257,3389,3557,3671,3833,3923,4001,4019,4397,4943,5099,5309,5441,5471

%N Primes q such that 10*q-1 and 10*q+3 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 9 and 3 in base 10.

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

%Y Cf. A046132, A342184, A342183.

%K nonn

%O 1,1

%A _Tamas Nagy_, Mar 04 2021