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A211641
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Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2>=n.
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2
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0, 1, 8, 27, 63, 124, 215, 339, 508, 725, 993, 1324, 1718, 2186, 2733, 3358, 4079, 4896, 5812, 6836, 7974, 9235, 10616, 12132, 13789, 15587, 17538, 19639, 21904, 24341, 26946, 29731, 32708, 35877, 39238, 42806, 46581, 50575, 54794, 59232
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OFFSET
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0,3
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COMMENTS
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For a guide to related sequences, see A211422.
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LINKS
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MATHEMATICA
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t = Compile[{{n, _Integer}}, Module[{s = 0},
(Do[If[w^2 + x^2 + y^2 >= n, s = s + 1],
{w, 1, #}, {x, 1, #}, {y, 1, #}] &[n]; s)]];
Map[t[#] &, Range[0, 80]] (* A211641 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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