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a(n) = Sum_{d|n, d=3 mod 4} d^4.
1

%I #10 Dec 06 2018 07:52:30

%S 0,0,81,0,0,81,2401,0,81,0,14641,81,0,2401,50706,0,0,81,130321,0,2482,

%T 14641,279841,81,0,0,531522,2401,0,50706,923521,0,14722,0,1503026,81,

%U 0,130321,2313522,0,0,2482,3418801,14641,50706,279841

%N a(n) = Sum_{d|n, d=3 mod 4} d^4.

%H Seiichi Manyama, <a href="/A050455/b050455.txt">Table of n, a(n) for n = 1..10000</a>

%t a[n_] := DivisorSum[n, #^4 &, Mod[#, 4]==3 &]; Array[a, 30] (* _Amiram Eldar_, Dec 06 2018 *)

%K nonn

%O 1,3

%A _N. J. A. Sloane_, Dec 23 1999