%I #12 Feb 24 2023 10:54:44
%S 251,1741,3301,3631,4051,5101,5281,5381,5531,6311,6361,6841,8641,9901,
%T 10861,11491,12451,12541,12641,13451,13591,14741,14891,15791,15901,
%U 16481,17471,18211,19471,22441,22811,23321,23761,24391,26171,26371,28921,29311,30091
%N Primes p such that four consecutive primes starting with p are congruent to {1,2,3,4} (mod 5).
%C Indices of primes: 54, 271, 464, 508, 559, 682, 701, 709, 732, 821, 829, 881, 1076, 1221, 1321, 1386, 1486, ....
%H Zak Seidov, <a href="/A215607/b215607.txt">Table of n, a(n) for n = 1..3000</a>
%e prime(54,55,56,57) = {251, 257, 263, 269} == {1,2,3,4} (mod 5).
%t nn = 4000; p = Partition[Prime[Range[nn]], 4, 1]; t = Select[p, Mod[#, 5] == {1, 2, 3, 4} &]; Transpose[t][[1]] (* _T. D. Noe_, Aug 17 2012 *)
%t Select[Partition[Prime[Range[4000]],4,1],Mod[#,5]=={1,2,3,4}&][[;;,1]] (* _Harvey P. Dale_, Feb 24 2023 *)
%Y Cf. A215599, A215662.
%K nonn
%O 1,1
%A _Zak Seidov_, Aug 17 2012
|