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A211642
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Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2<2n.
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2
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0, 0, 1, 1, 4, 7, 10, 11, 17, 20, 26, 32, 35, 38, 48, 54, 60, 66, 75, 78, 87, 96, 105, 114, 120, 127, 139, 145, 157, 169, 178, 184, 196, 202, 217, 232, 238, 244, 263, 278, 284, 296, 308, 314, 329, 347, 365, 371, 383, 389, 410, 428, 434, 452, 467, 477
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OFFSET
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0,5
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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 < 2 n, s = s + 1],
{w, 1, #}, {x, 1, #}, {y, 1, #}] &[n]; s)]];
Map[t[#] &, Range[0, 80]] (* A211642 *)
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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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