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A211631 Number of ordered triples (w,x,y) with all terms in {-n,...-1,1,...,n} and w^2>x^2+y^2.

%I A211631 #6 Dec 04 2016 19:46:27
%S A211631 0,0,8,40,104,208,384,624,952,1384,1920,2584,3368,4304,5416,6696,8160,
%T A211631 9808,11680,13784,16120,18696,21552,24672,28064,31752,35768,40128,
%U A211631 44808,49816,55200,60952,67112,73664,80624,88032,95848,104120
%N A211631 Number of ordered triples (w,x,y) with all terms in {-n,...-1,1,...,n} and w^2>x^2+y^2.
%C A211631 For a guide to related sequences, see A211422.
%t A211631 t = Compile[{{u, _Integer}},
%t A211631    Module[{s = 0}, (Do[If[w^2 > x^2 + y^2,
%t A211631          s = s + 1], {w, #}, {x, #}, {y, #}] &[
%t A211631       Flatten[{Reverse[-#], #} &[Range[1, u]]]]; s)]];
%t A211631 Map[t[#] &, Range[0, 50]]  (* A211631 *)
%t A211631 %/8                        (* integers *)
%t A211631 (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y A211631 Cf. A211422.
%K A211631 nonn
%O A211631 0,3
%A A211631 _Clark Kimberling_, Apr 17 2012