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A363025
Sum of divisors of 5*n-2 of form 5*k+2.
4
0, 2, 0, 2, 0, 9, 0, 2, 0, 14, 0, 2, 7, 19, 0, 2, 0, 24, 0, 9, 0, 41, 0, 2, 0, 34, 7, 2, 0, 39, 17, 2, 0, 63, 0, 2, 0, 49, 0, 24, 7, 54, 0, 2, 0, 71, 0, 26, 27, 64, 0, 2, 0, 69, 7, 2, 0, 118, 0, 2, 0, 108, 0, 2, 17, 84, 37, 2, 7, 101, 0, 2, 0, 94, 0, 78, 0, 99, 0, 2, 0, 133, 7, 24, 47, 109, 0, 2, 0, 153, 0
OFFSET
1,2
FORMULA
a(n) = A284280(5*n-2).
G.f.: Sum_{k>0} (5*k-3) * x^(4*k-2) / (1 - x^(5*k-3)).
MATHEMATICA
a[n_] := DivisorSum[5*n - 2, # &, Mod[#, 5] == 2 &]; Array[a, 100] (* Amiram Eldar, Jul 06 2023 *)
PROG
(PARI) a(n) = sumdiv(5*n-2, d, (d%5==2)*d);
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jul 06 2023
STATUS
approved