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A050455
a(n) = Sum_{d|n, d=3 mod 4} d^4.
1
0, 0, 81, 0, 0, 81, 2401, 0, 81, 0, 14641, 81, 0, 2401, 50706, 0, 0, 81, 130321, 0, 2482, 14641, 279841, 81, 0, 0, 531522, 2401, 0, 50706, 923521, 0, 14722, 0, 1503026, 81, 0, 130321, 2313522, 0, 0, 2482, 3418801, 14641, 50706, 279841
OFFSET
1,3
LINKS
MATHEMATICA
a[n_] := DivisorSum[n, #^4 &, Mod[#, 4]==3 &]; Array[a, 30] (* Amiram Eldar, Dec 06 2018 *)
CROSSREFS
Sequence in context: A116230 A056669 A005085 * A110727 A005068 A366458
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 23 1999
STATUS
approved