A211922 Number of (w,x,y,z) with all terms in {1,...,n} and 2*w*x>3*y*z.

0, 0, 5, 23, 80, 218, 456, 865, 1505, 2428, 3732, 5522, 7841, 10877, 14710, 19424, 25221, 32282, 40624, 50551, 62171, 75686, 91309, 109293, 129662, 152868, 179061, 208361, 241167, 277832, 318330, 363247, 412725, 467063, 526644, 591736, 662511, 739687, 823382

Offset

0,3

Comments

a(n)+A211921(n)=n^4.

See A211795 for a guide to related sequences.

Links

Table of n, a(n) for n=0..38.

Mathematica

t = Compile[{{n, _Integer}}, Module[{s = 0},
(Do[If[2 w*x > 3 y*z, s = s + 1],
{w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
Map[t[#] &, Range[0, 40]] (* A211922 *)
(* Peter J. C. Moses, Apr 13 2012 *)

Crossrefs

Cf. A211795.

Sequence in context: A293426 A267202 A211809 * A139209 A227123 A113946

Adjacent sequences: A211919 A211920 A211921 * A211923 A211924 A211925

Keyword

nonn

Author

Clark Kimberling, Apr 28 2012

Status

approved