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%I #5 Dec 04 2016 19:46:28
%S 0,0,0,8,14,18,48,56,74,126,154,166,262,278,318,422,480,500,674,698,
%T 800,956,1024,1052,1308,1378,1458,1698,1852,1888,2240,2280,2434,2686,
%U 2794,2950,3472,3520,3640,3944,4234,4286,4800,4856,5102,5672
%N Number of (w,x,y,z) with all terms in {1,...,n} and w*x=3*y*z.
%C Each term is divisible by 2. See A211795 for a guide to related sequences.
%t t = Compile[{{n, _Integer}}, Module[{s = 0},
%t (Do[If[w*x == 3 y*z, s = s + 1],
%t {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t Map[t[#] &, Range[0, 50]] (* A212020 *)
%t %/2 (* integers *)
%t (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y Cf. A211795.
%K nonn
%O 0,4
%A _Clark Kimberling_, Apr 28 2012
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