A058269 An approximation to sigma_{3/2}(n): floor( sum_{d|n} d^(3/2) ).

1, 3, 6, 11, 12, 23, 19, 34, 33, 46, 37, 73, 47, 74, 75, 98, 71, 127, 83, 144, 120, 143, 111, 213, 137, 183, 173, 230, 157, 288, 173, 279, 232, 272, 237, 392, 226, 320, 296, 419, 263, 463, 282, 443, 404, 426, 323, 610, 362, 525, 440, 566, 386

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Formula

Sum_{k=1..n} a(k) ~ (2/5)*zeta(5/2) * n^(5/2). - Amiram Eldar, Jan 14 2023

Maple

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)

Mathematica

a[n_] := Floor[DivisorSigma[3/2, n]]; Array[a, 50] (* Amiram Eldar, Jan 14 2023 *)

Crossrefs

Cf. A000203, A001157, A058270, A058271, A247041.

Sequence in context: A332933 A115821 A115767 * A342273 A310088 A073942

Adjacent sequences: A058266 A058267 A058268 * A058270 A058271 A058272

Keyword

nonn

Author

N. J. A. Sloane, Dec 08 2000

Status

approved