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A211919 Number of (w,x,y,z) with all terms in {1,...,n} and w*x>=3*y*z.

%I A211919 #9 Dec 04 2016 19:46:28
%S A211919 0,0,1,14,46,118,267,497,871,1438,2215,3273,4713,6526,8844,11758,
%T A211919 15303,19590,24796,30862,38053,46457,56115,67206,79971,94357,110628,
%U A211919 128979,149481,172291,197776,225789,256763,290878,328179,369011
%N A211919 Number of (w,x,y,z) with all terms in {1,...,n} and w*x>=3*y*z.
%C A211919 a(n)+A211920(n)=n^4.
%C A211919 See A211795 for a guide to related sequences.
%t A211919 t = Compile[{{n, _Integer}}, Module[{s = 0},
%t A211919 (Do[If[w*x >= 3 y*z, s = s + 1], {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t A211919 Map[t[#] &, Range[0, 40]] (* A211919 *)
%t A211919 (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y A211919 Cf. A211795.
%K A211919 nonn
%O A211919 0,4
%A A211919 _Clark Kimberling_, Apr 28 2012