A212100 Number of (w,x,y,z) with all terms in {1,...,n} and w^3>=x^3+y^3+z^3.

0, 0, 1, 9, 35, 89, 198, 373, 651, 1059, 1632, 2407, 3432, 4767, 6453, 8536, 11097, 14189, 17906, 22308, 27451, 33438, 40332, 48291, 57313, 67602, 79200, 92187, 106774, 122952, 140954, 160835, 182772, 206869, 233238, 262110, 293535

Offset

0,4

Comments

a(n)+A212097(n)=n^4. For a guide to related sequences, see A211795.

Links

Table of n, a(n) for n=0..36.

Mathematica

t = Compile[{{n, _Integer}}, Module[{s = 0},
(Do[If[w^3 >= x^3 + y^3 + z^3, s = s + 1],
{w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
Map[t[#] &, Range[0, 40]] (* A212100 *)
(* Peter J. C. Moses, Apr 13 2012 *)

Crossrefs

Cf. A211795.

Sequence in context: A022275 A071398 A212099 * A005898 A034957 A180082

Adjacent sequences: A212097 A212098 A212099 * A212101 A212102 A212103

Keyword

nonn

Author

Clark Kimberling, May 03 2012

Status

approved