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 A102269 #11 Mar 14 2024 03:50:06
%S A102269 43,67,79,127,151,163,211,331,379,463,487,499,547,571,631,739,751,823,
%T A102269 883,907,919,967,991,1051,1087,1171,1303,1327,1423,1471,1579,1663,
%U A102269 1723,1747,1759,1831,1999,2011,2083,2143,2179,2251,2311,2347,2503,2647,2671,2683,2731,2767,2851,3019
%N A102269 Primes p such that Q(sqrt(-21p)) has genus characters chi_{-3} = +1, chi_{-7} = +1.
%C A102269 Primes p such that p is 3 (mod 4) and (-3/p) = (-7/p) = 1, where (k/n) is the Kronecker symbol. - _Robin Visser_, Mar 13 2024
%H A102269 H. Cohn and J. C. Lagarias, <a href="http://doi.org/10.1090/S0025-5718-1983-0717716-8">On the existence of fields governing the 2-invariants of the classgroup of Q(sqrt{dp}) as p varies</a>, Math. Comp. 41 (1983), 711-730.
%F A102269 The primes are congruent to {43, 67, 79} (mod 84). - _Robin Visser_, Mar 13 2024
%o A102269 (Magma) [p : p in PrimesUpTo(3000) | p mod 84 in [43, 67, 79]]; // _Robin Visser_, Mar 13 2024
%Y A102269 Cf. A102270, A102271, A102272, A102273, A102274, A102275.
%K A102269 nonn
%O A102269 1,1
%A A102269 _N. J. A. Sloane_, Feb 19 2005
%E A102269 More terms from _Robin Visser_, Mar 13 2024