A274559 Numbers k such that sigma(k) == 0 (mod k+7).

8, 272, 7232, 30848, 516608, 134094848, 2146992128, 35184309174272

Offset: 1

Author

Paolo P. Lava, Jul 05 2016

Keywords

• nonn
• more

Examples

			sigma(8) mod (8+7) = 15 mod 15 = 0.
		

Crossrefs

Contains subsequence A141546.

Cf. A045770, A067702, A088833, A181598, A274551, A274552, A274553, A274554, A274556, A274557, A274558, A274560, A274561, A274562, A274563, A274564, A274565, A274566.

Programs

Mathematica

Select[Range[10^6], Mod[DivisorSigma[1, #], # + 7] == 0 &] (* Michael De Vlieger, Jul 05 2016 *)

Extensions

a(6)-a(7) from Giovanni Resta, Jul 05 2016

a(8) from Max Alekseyev, May 29 2025