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A211631
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Number of ordered triples (w,x,y) with all terms in {-n,...-1,1,...,n} and w^2>x^2+y^2.
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2
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0, 0, 8, 40, 104, 208, 384, 624, 952, 1384, 1920, 2584, 3368, 4304, 5416, 6696, 8160, 9808, 11680, 13784, 16120, 18696, 21552, 24672, 28064, 31752, 35768, 40128, 44808, 49816, 55200, 60952, 67112, 73664, 80624, 88032, 95848, 104120
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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[{{u, _Integer}},
Module[{s = 0}, (Do[If[w^2 > x^2 + y^2,
s = s + 1], {w, #}, {x, #}, {y, #}] &[
Flatten[{Reverse[-#], #} &[Range[1, u]]]]; s)]];
Map[t[#] &, Range[0, 50]] (* A211631 *)
%/8 (* integers *)
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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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