This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A195379 #14 Jun 13 2021 08:10:11 %S A195379 2,137,281,521,641,883,937,1087,1151,1229,1277,1301,1489,1567,1607, %T A195379 1697,2027,2081,2237,2381,2543,2591,2657,2687,2729,2801,2851,2969, %U A195379 3119,3257,3301,3359,3463,3467,3529,3673,3733,3793,3821,3851,4073,4217,4229,4241,4259,4283,4337,4421,4481 %N A195379 3.5-gap primes: Primes prime(k) such that there is no prime between 7*prime(k)/2 and 7*prime(k+1)/2. %t A195379 Select[Prime[Range[1000]], PrimePi[7*NextPrime[#]/2] == PrimePi[7*#/2] &] (* _T. D. Noe_, Sep 20 2011 *) %Y A195379 Cf. A080192, A195270, A195271, A195377, A195325, A195329, A193507, A194186, A164368, A194598, A194658, A194659, A194674, A164288, A164294. %K A195379 nonn %O A195379 1,1 %A A195379 _Vladimir Shevelev_, Sep 17 2011 %E A195379 Corrected by _R. J. Mathar_, Sep 20 2011