A060903 a(n) = floor(6*n*sqrt(n)/Pi^2).

0, 0, 1, 3, 4, 6, 8, 11, 13, 16, 19, 22, 25, 28, 31, 35, 38, 42, 46, 50, 54, 58, 62, 67, 71, 75, 80, 85, 90, 94, 99, 104, 110, 115, 120, 125, 131, 136, 142, 148, 153, 159, 165, 171, 177, 183, 189, 195, 202, 208, 214, 221, 227, 234, 241, 247, 254, 261, 268, 275, 282

Offset

0,4

Comments

Conjecture: the sum of the divisors of n is less than a(n) for n exceeding 12. - Robert G. Wilson v, May 14 2014

Links

Harry J. Smith, Table of n, a(n) for n = 0..1000

Formula

a(n) = A000203(n) + A058208(n).

a(n) = floor(6*n^(3/2)/Pi^2).

Mathematica

f[n_] := Floor[6 n^(3/2)/Pi^2]; Array[f, 61, 0] (* Robert G. Wilson v, May 14 2014 *)

Prog

(PARI) { default(realprecision, 100); t=Pi^2/6; for (n=0, 1000, write("b060903.txt", n, " ", n*sqrt(n)\t); ) } \\ Harry J. Smith, Jul 14 2009

Crossrefs

Cf. A000093, A000203, A000796, A058208.

Sequence in context: A186154 A030711 A030761 * A079401 A156040 A325172

Adjacent sequences: A060900 A060901 A060902 * A060904 A060905 A060906

Keyword

nonn,changed

Author

Henry Bottomley, May 05 2001

Status

approved