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A212097
Number of (w,x,y,z) with all terms in {1,...,n} and w^3<x^3+y^3+z^3.
3
0, 1, 15, 72, 221, 536, 1098, 2028, 3445, 5502, 8368, 12234, 17304, 23794, 31963, 42089, 54439, 69332, 87070, 108013, 132549, 161043, 193924, 231550, 274463, 323023, 377776, 439254, 507882, 584329, 669046, 762686, 865804, 979052
OFFSET
0,3
COMMENTS
a(n)+A212100(n)=4^n. For a guide to related sequences, see A211795.
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]] (* A212097 *)
(* Peter J. C. Moses, Apr 13 2012 *)
CROSSREFS
Cf. A211795.
Sequence in context: A168298 A126274 A241234 * A212098 A053531 A000476
KEYWORD
nonn
AUTHOR
Clark Kimberling, May 03 2012
STATUS
approved