A274563 Numbers k such that sigma(k) == 0 (mod k+9).

15, 208, 6976, 8415, 31815, 351351, 2077696, 20487159, 159030135, 536559616, 2586415095, 137433972736, 2199003332608, 2305842988812599296, 151115727446605966606336

Offset

1,1

Links

Table of n, a(n) for n=1..15.

Example

sigma(15) mod (15 + 9) = 24 mod 24 = 0.

Mathematica

Select[Range[10^6], Mod[DivisorSigma[1, #], # + 9] == 0 &] (* Michael De Vlieger, Jul 06 2016 *)

Prog

(PARI) isok(k) = !(sigma(k) % (k+9)); \\ Michel Marcus, Oct 14 2025

Crossrefs

Contains subsequence A223610.

Cf. A045770, A067702, A088833, A181598, A274551-A274562, A274564-A274566.

Sequence in context: A051813 A280160 A239991 * A122572 A028230 A067560

Adjacent sequences: A274560 A274561 A274562 * A274564 A274565 A274566

Keyword

nonn,more

Author

Paolo P. Lava, Jul 06 2016

Extensions

a(7)-a(13) from Giovanni Resta, Jul 06 2016

a(14)-a(15) from Max Alekseyev, Jan 30 2026

Status

approved