A142854 - OEIS

%I #13 Feb 21 2024 13:52:20

%S 239,727,971,1093,1459,2069,2557,2801,3167,3533,4021,5119,5851,6217,

%T 6827,6949,7193,7559,7681,8291,8779,9511,10243,10487,10853,12073,

%U 13049,13171,13537,13781,13903,14879,15733,16831,17807,17929,18539,18661,19759,20369

%N Primes congruent to 56 mod 61.

%C Primes 6217 and 13537 are such that p!-2^p+1 is (probably) prime. - _M. F. Hasler_, Apr 09 2015

%H Vincenzo Librandi, <a href="/A142854/b142854.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime[Range[2600]], MemberQ[{56}, Mod[#, 61]] &] (* _Vincenzo Librandi_, Sep 05 2012 *)

%t Select[Range[56,21000,61],PrimeQ] (* _Harvey P. Dale_, Feb 21 2024 *)

%o (Magma) [p: p in PrimesUpTo(21000) | p mod 61 eq 56 ] ; // _Vincenzo Librandi_, Sep 05 2012

%o (PARI) select(p->p%61==56,primes(2000)) \\ _M. F. Hasler_, Apr 09 2015

%Y Cf. A000040.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_, Jul 11 2008