A332226 Numbers k such that sigma(k) is congruent to 2 modulo 8.

10, 17, 20, 26, 40, 41, 52, 58, 73, 74, 80, 89, 90, 97, 104, 106, 113, 116, 122, 137, 148, 153, 160, 180, 193, 202, 208, 212, 218, 232, 233, 234, 241, 244, 257, 281, 296, 298, 313, 314, 320, 325, 337, 346, 353, 360, 362, 369, 394, 401, 404, 409, 416, 424, 433, 436, 449, 457, 458, 464, 468, 488, 490, 521, 522, 538, 554

Offset: 1

Author

Antti Karttunen, Feb 13 2020

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..25000
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000203.

Subsequence of A191217.

Subsequences: A332227 (odd terms), A332228.

Programs

Mathematica

Select[Range[600],Mod[DivisorSigma[1,#],8]==2&] (* Harvey P. Dale, Mar 30 2025 *)

PARI

isA332226(n) = (2==(sigma(n)%8));