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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.
2

%I #5 Dec 04 2016 19:46:27

%S 0,0,1,1,4,7,10,11,17,20,26,32,35,38,48,54,60,66,75,78,87,96,105,114,

%T 120,127,139,145,157,169,178,184,196,202,217,232,238,244,263,278,284,

%U 296,308,314,329,347,365,371,383,389,410,428,434,452,467,477

%N Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2<2n.

%C For a guide to related sequences, see A211422.

%t t = Compile[{{n, _Integer}}, Module[{s = 0},

%t (Do[If[w^2 + x^2 + y^2 < 2 n, s = s + 1],

%t {w, 1, #}, {x, 1, #}, {y, 1, #}] &[n]; s)]];

%t Map[t[#] &, Range[0, 80]] (* A211642 *)

%t (* _Peter J. C. Moses_, Apr 13 2012 *)

%Y Cf. A211422.

%K nonn

%O 0,5

%A _Clark Kimberling_, Apr 18 2012