%I #8 Dec 04 2016 19:46:29
%S 0,0,1,1,14,18,31,35,80,96,125,133,216,228,269,309,444,460,543,559,
%T 720,784,853,873,1142,1202,1287,1363,1596,1624,1831,1859,2206,2314,
%U 2427,2559,2962,2998,3123,3247,3758,3798,4103,4143,4524,4772,4925,4969,5712,5836
%N Number of (w,x,y,z) with all terms in {1,...,n} and w*x=4*y*z.
%C See A211795 for a guide to related sequences.
%t t = Compile[{{n, _Integer}}, Module[{s = 0},
%t (Do[If[w*x == 4 y*z, s = s + 1],
%t {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t Map[t[#] &, Range[0, 50]] (* A212047 *)
%t (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y Cf. A211795.
%K nonn
%O 0,5
%A _Clark Kimberling_, Apr 28 2012
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