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%I #17 Jul 08 2023 08:04:51
%S 0,0,3,0,0,10,0,0,14,0,0,18,7,0,22,0,0,26,0,18,30,0,0,34,0,0,60,0,0,
%T 42,11,0,46,26,0,50,0,0,54,0,30,84,0,0,62,0,0,100,0,0,70,0,30,74,38,0,
%U 93,0,0,82,0,42,86,34,0,90,0,0,140,0,0,132,0,0,140,50,0,106,0,0,110,0,54,114,0,42,156
%N Sum of divisors of 4*n-3 of form 4*k+3.
%F a(n) = A050452(4*n-3).
%F G.f.: Sum_{k>0} (4*k-1) * x^(3*k) / (1 - x^(4*k-1)).
%t a[n_] := DivisorSum[4*n - 3, # &, Mod[#, 4] == 3 &]; Array[a, 100] (* _Amiram Eldar_, Jul 08 2023 *)
%o (PARI) a(n) = sumdiv(4*n-3, d, (d%4==3)*d);
%Y Cf. A050452, A359240, A364084.
%K nonn
%O 1,3
%A _Seiichi Manyama_, Jul 08 2023