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A058270
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An approximation to sigma_{3/2}(n): round( sum_{d|n} d^(3/2) ).
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4
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1, 4, 6, 12, 12, 24, 20, 34, 33, 47, 37, 73, 48, 75, 75, 98, 71, 127, 84, 144, 121, 144, 111, 213, 137, 183, 173, 231, 157, 289, 174, 279, 232, 272, 238, 393, 226, 321, 297, 420, 264, 463, 283, 443, 404, 426, 323, 610, 363, 525, 441, 566, 387
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OFFSET
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1,2
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LINKS
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FORMULA
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Sum_{k=1..n} a(k) ~ (2/5)*zeta(5/2) * n^(5/2). - Amiram Eldar, Jan 14 2023
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MAPLE
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f := proc(n) local d, t1, t2; t2 := 0; t1 := divisors(n); for d in t1 do t2 := t2 + d^(3/2) end do; t2; end proc; # exact value of sigma_{3/2}(n)
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MATHEMATICA
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a[n_] := Round[DivisorSigma[3/2, n]]; Array[a, 50] (* Amiram Eldar, Jan 14 2023 *)
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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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