A351533 Odd numbers k that are multiples of 3 and for which sigma(k) is congruent to 2 modulo 4.

45, 117, 153, 261, 333, 369, 405, 477, 549, 657, 801, 873, 909, 981, 1017, 1053, 1233, 1341, 1377, 1413, 1557, 1629, 1737, 1773, 2061, 2097, 2169, 2205, 2313, 2349, 2421, 2493, 2529, 2637, 2817, 2853, 2925, 2997, 3033, 3141, 3177, 3321, 3357, 3501, 3573, 3609, 3645, 3681, 3789, 3825, 3897, 4041, 4113, 4149, 4293

Offset

1,1

Links

Table of n, a(n) for n=1..55.

Index entries for sequences related to sigma(n)

Mathematica

Select[3*Range[1, 1400, 2], Mod[DivisorSigma[1, #], 4] == 2 &] (* Amiram Eldar, Feb 13 2022 *)

Prog

(PARI) isA351533(n) = ((n%2) && !(n%3) && (2 == (sigma(n)%4)));

Crossrefs

Intersection of A008585 and A191218. Complement of A351535 in A191218.

Cf. A351534 (subsequence).

Sequence in context: A044613 A039528 A228058 * A074770 A348939 A370914

Adjacent sequences: A351530 A351531 A351532 * A351534 A351535 A351536

Keyword

nonn

Author

Antti Karttunen, Feb 13 2022

Status

approved