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 A109556 #5 Jun 03 2025 01:08:33
%S A109556 3,5,11,17,79,97,103,109,127,163,193,223,229,277,307,313,349,379,397,
%T A109556 439,457,463,487,499,613,643,677,727,733,751,941,947,971,977,991,1013,
%U A109556 1033,1063,1097,1103,1117,1123,1181,1187,1217,1223,1231,1283,1291,1321
%N A109556 prime(k) for those k where floor((2*(prime(k+1)-prime(k))*PrimePi(k) mod (8*k))/k) = m with m = 2.
%t A109556 a = Flatten[Table[If[Floor[2*Mod[(Prime[n + 1] - Prime[n])*PrimePi[n]/n, 8]] == 2, Prime[n], {}], {n, 1, 400}]]
%Y A109556 Cf. A000040, A000720, A001359.
%Y A109556 Cf. A109556-A109569 for m = 2..15.
%K A109556 nonn,less
%O A109556 1,1
%A A109556 _Roger L. Bagula_, Jun 27 2005
%E A109556 Name edited and offset corrected by _Amiram Eldar_, Jun 02 2025