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%I #5 Dec 04 2016 19:46:29
%S 0,0,0,0,0,20,32,36,46,54,118,126,162,170,194,316,358,370,430,442,614,
%T 666,714,730,840,1064,1124,1184,1276,1296,1686,1710,1824,1908,1980,
%U 2320,2524,2552,2636,2732,3202,3234,3470,3502,3658,4222,4330
%N Number of (w,x,y,z) with all terms in {1,...,n} and 2w*x=5*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[2 w*x == 5 y*z, s = s + 1],
%t {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t Map[t[#] &, Range[0, 50]] (* A212050 *)
%t %/2 (* integers *)
%t (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y Cf. A211795.
%K nonn
%O 0,6
%A _Clark Kimberling_, Apr 29 2012
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