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A363034
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Sum of divisors of 5*n-2 of form 5*k+3.
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4
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3, 8, 13, 21, 23, 28, 36, 38, 43, 59, 53, 58, 66, 68, 73, 94, 83, 96, 96, 98, 103, 129, 113, 118, 126, 136, 133, 164, 156, 148, 156, 158, 163, 207, 173, 178, 186, 188, 193, 252, 203, 229, 216, 218, 223, 269, 233, 238, 246, 256, 276, 304, 263, 268, 289, 278, 283, 365, 293, 298, 306, 336, 313, 374, 323
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OFFSET
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1,1
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LINKS
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FORMULA
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G.f.: Sum_{k>0} (5*k-2) * x^k / (1 - x^(5*k-2)).
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MATHEMATICA
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a[n_] := DivisorSum[5*n - 2, # &, Mod[#, 5] == 3 &]; Array[a, 100] (* Amiram Eldar, Jul 06 2023 *)
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PROG
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(PARI) a(n) = sumdiv(5*n-2, d, (d%5==3)*d);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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