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 A140180 #10 Apr 09 2014 10:14:40 %S A140180 1,2,5,10,11,13,16,22,23,25,26,28,29,33,35,36,39,40,41,43,46,50,52,53, %T A140180 56,58,61,63,65,66,67,70,73,78,81,82,83,86,88,89,92,93,95,96,100,101, %U A140180 105,106,111,112,113,116,119,122,124,125,126,127,130,131,134,136,145 %N A140180 A number n is included if the smallest prime that is congruent to 1 (mod n) is <= the smallest prime that is congruent to -1 (mod n). %H A140180 Diana Mecum, <a href="/A140180/b140180.txt">Table of n, a(n) for n = 1..567</a> %e A140180 For n = 1 and 2 the smallest prime that is congruent to 1 (mod n) equals the smallest prime that is congruent to -1 (mod n). For all other n the inequality is strict. %Y A140180 Cf. A093868, A140181. %K A140180 nonn %O A140180 1,2 %A A140180 _Leroy Quet_, May 11 2008 %E A140180 More terms from _Diana L. Mecum_, Jul 04 2008