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A212255 Number of (w,x,y,z) with all terms in {1,...,n} and 3w^2 = x^2 + y^2 + z^2. 2

%I

%S 0,1,2,3,4,8,9,16,17,18,22,32,33,43,50,54,55,68,69,85,89,96,106,125,

%T 126,151,161,162,169,191,195,220,221,231,244,284,285,313,329,339,343,

%U 380,387,415,425,429,448,485,486,523,548,561,571,611,612,685,692

%N Number of (w,x,y,z) with all terms in {1,...,n} and 3w^2 = x^2 + y^2 + z^2.

%C w^2 = average of x^2, y^2, z^2. For a guide to related sequences, see A211795.

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

%t (Do[If[3 w^2 == x^2 + y^2 + z^2, s = s + 1],

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

%t Map[t[#] &, Range[0, 60]] (* A212255 *)

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

%Y Cf. A211795.

%K nonn

%O 0,3

%A _Clark Kimberling_, May 15 2012

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Last modified February 19 16:24 EST 2020. Contains 332045 sequences. (Running on oeis4.)