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A211921 Number of (w,x,y,z) with all terms in {1,...,n} and 2w*x<=3*y*z.

%I A211921 #8 Dec 04 2016 19:46:28
%S A211921 0,1,11,58,176,407,840,1536,2591,4133,6268,9119,12895,17684,23706,
%T A211921 31201,40315,51239,64352,79770,97829,118795,142947,170548,202114,
%U A211921 237757,277915,323080,373489,429449,491670,560274,635851,718858,809692
%N A211921 Number of (w,x,y,z) with all terms in {1,...,n} and 2w*x<=3*y*z.
%C A211921 a(n)+A211922(n)=n^4.
%C A211921 See A211795 for a guide to related sequences.
%t A211921 t = Compile[{{n, _Integer}}, Module[{s = 0},
%t A211921 (Do[If[2 w*x <= 3 y*z, s = s + 1],
%t A211921 {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t A211921 Map[t[#] &, Range[0, 40]] (* A211921 *)
%t A211921 (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y A211921 Cf. A211795.
%K A211921 nonn
%O A211921 0,3
%A A211921 _Clark Kimberling_, Apr 28 2012