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A362952
Sum of divisors of 5*n-1 of form 5*k+2.
4
2, 0, 9, 0, 14, 0, 19, 0, 24, 7, 29, 0, 34, 0, 39, 0, 63, 0, 49, 0, 54, 0, 59, 24, 64, 0, 69, 0, 86, 0, 108, 0, 84, 0, 89, 0, 94, 34, 99, 0, 133, 0, 109, 0, 153, 0, 119, 0, 124, 0, 129, 44, 168, 0, 139, 0, 144, 17, 198, 0, 154, 0, 159, 0, 203, 54, 169, 0, 174, 0, 179, 0, 243, 0, 228, 0, 238, 0, 199, 64, 204
OFFSET
1,1
FORMULA
a(n) = A284280(5*n-1).
G.f.: Sum_{k>0} (5*k-3) * x^(2*k-1) / (1 - x^(5*k-3)).
MATHEMATICA
a[n_] := DivisorSum[5*n - 1, # &, Mod[#, 5] == 2 &]; Array[a, 100] (* Amiram Eldar, Jul 06 2023 *)
PROG
(PARI) a(n) = sumdiv(5*n-1, d, (d%5==2)*d);
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jul 06 2023
STATUS
approved