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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.

A274565 Numbers k such that sigma(k) == 0 (mod k+10).

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%I A274565 #29 Jun 09 2025 10:27:44
%S A274565 14,176,1376,3230,3770,6848,114256,125696,544310,561824,740870,
%T A274565 2075648,4199030,4607296,8436950,33468416,134045696,199272950,
%U A274565 624032630,1113445430,1550860550,85905593344,2199001235456,35184284008448
%N A274565 Numbers k such that sigma(k) == 0 (mod k+10).
%e A274565 sigma(14) mod (14 + 10) = 24 mod 24 = 0.
%t A274565 k = 10; Select[Range[Abs@k+1, 10^6], Mod[DivisorSigma[1, #], # + k] == 0 &] (* _Vincenzo Librandi_, Jul 06 2016 *)
%o A274565 (Magma) [n: n in [1..2*10^6] | SumOfDivisors(n) mod (n+10) eq 0 ]; // _Vincenzo Librandi_, Jul 06 2016
%Y A274565 Contains subsequence A223611.
%Y A274565 Contains 2 * odd terms of A223609.
%Y A274565 Cf. A045770, A067702, A088833, A181598, A274551, A274552, A274553, A274554, A274556, A274557, A274558, A274559, A274560, A274561, A274562, A274563, A274564, A274566.
%K A274565 nonn,more
%O A274565 1,1
%A A274565 _Paolo P. Lava_, Jul 06 2016
%E A274565 a(13)-a(23) from _Giovanni Resta_, Jul 06 2016
%E A274565 a(24) from _Max Alekseyev_, May 29 2025