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 A327636 #25 Sep 08 2022 08:46:24
%S A327636 0,1,313,30853,42992,247753,584989,4130748,4390945,4780473,5871073,
%T A327636 7615813,8123113,13514233,13971013,19128653,19392433,43794833,
%U A327636 51644173,67314973,69522073,108168073,124498753,124510153,177694105,198750308,208302253,212791885,230815033
%N A327636 Numbers k such that 2k + 1 divides 2^k + k^2.
%C A327636 2*a(n) + 1: 1, 3, 627, 61707, 85985, 495507, 1169979, 8261497, ...
%t A327636 Do[ k=2*n+1; f=PowerMod[ 2, n, k ] + PowerMod[ n, 2, k ]; If[ IntegerQ[ f/k ], Print[ n ] ], {n, 0, 10^7} ] (* _Metin Sariyar_, Sep 21 2019 *)
%o A327636 (Magma) [n: n in [0..100000] | Denominator((2^n+n^2)/(2*n+1)) eq 1];
%o A327636 (PARI) is(n) = Mod(2, 2*n+1)^n==-n^2 \\ _Felix Fröhlich_, Sep 20 2019
%Y A327636 Cf. A001580, A242776.
%K A327636 nonn
%O A327636 1,3
%A A327636 _Juri-Stepan Gerasimov_, Sep 20 2019
%E A327636 More terms from _Felix Fröhlich_, Sep 20 2019
%E A327636 Offset 1 from _Michel Marcus_, Jul 02 2021