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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.

A274561 Numbers k such that sigma(k) == 0 (mod k+8).

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%I A274561 #18 Jun 10 2025 16:58:05
%S A274561 10,49,240,550,748,1504,3192,7192,7912,10792,17272,30592,979992,
%T A274561 1713592,4526272,8353792,9928792,11547352,17999992,89283592,173482552,
%U A274561 361702144,1081850752,1845991216,2146926592,11097907192,12985220152,21818579968,34357510144,109170719992,228354264064,279632332792,549746900992,1511712719992,2169800814592
%N A274561 Numbers k such that sigma(k) == 0 (mod k+8).
%e A274561 sigma(10) mod (10 + 8) = 18 mod 18 = 0.
%t A274561 Select[Range[10^6], Mod[DivisorSigma[1, #], # + 8] == 0 &] (* _Michael De Vlieger_, Jul 05 2016 *)
%Y A274561 Cf. A000203, A045770, A067702, A088833, A181598, A274551-A274560, A274562-A274566.
%K A274561 nonn
%O A274561 1,1
%A A274561 _Paolo P. Lava_, Jul 05 2016
%E A274561 a(16)-a(35) from _Giovanni Resta_