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 A274559 #29 Jun 14 2025 12:12:13 %S A274559 8,272,7232,30848,516608,134094848,2146992128,35184309174272 %N A274559 Numbers k such that sigma(k) == 0 (mod k+7). %e A274559 sigma(8) mod (8+7) = 15 mod 15 = 0. %t A274559 Select[Range[10^6], Mod[DivisorSigma[1, #], # + 7] == 0 &] (* _Michael De Vlieger_, Jul 05 2016 *) %Y A274559 Contains subsequence A141546. %Y A274559 Cf. A045770, A067702, A088833, A181598, A274551, A274552, A274553, A274554, A274556, A274557, A274558, A274560, A274561, A274562, A274563, A274564, A274565, A274566. %K A274559 nonn,more %O A274559 1,1 %A A274559 _Paolo P. Lava_, Jul 05 2016 %E A274559 a(6)-a(7) from _Giovanni Resta_, Jul 05 2016 %E A274559 a(8) from _Max Alekseyev_, May 29 2025