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%I #7 Dec 04 2016 19:46:28
%S 0,1,15,75,224,525,1077,1960,3299,5249,7939,11534,16285,22313,29890,
%T 39289,50713,64431,80854,100157,122747,148980,179165,213687,253113,
%U 297646,347806,404160,467027,536878,614464,700012,794247,897729
%N Number of 4-tuples (w,x,y,z) with all terms in {1,...,n} and w*x<=3*y*z.
%C a(n)+A211918(n)=n^4.
%C 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, 40]] (* A211812 *)
%t (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y Cf. A211795.
%K nonn
%O 0,3
%A _Clark Kimberling_, Apr 27 2012
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