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A211917 Number of (w,x,y,z) with all terms in {1,...,n} and w*x<3*y*z.

%I A211917 #8 Dec 04 2016 19:46:28
%S A211917 0,1,15,67,210,507,1029,1904,3225,5123,7785,11368,16023,22035,29572,
%T A211917 38867,50233,63931,80180,99459,121947,148024,178141,212635,251805,
%U A211917 296268,346348,402462,465175,534990,612224,697732,791813,895043
%N A211917 Number of (w,x,y,z) with all terms in {1,...,n} and w*x<3*y*z.
%C A211917 a(n)+A211919(n)=n^4.
%C A211917 See A211795 for a guide to related sequences.
%t A211917 t = Compile[{{n, _Integer}}, Module[{s = 0},
%t A211917 (Do[If[w*x < 3 y*z, s = s + 1],
%t A211917 {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t A211917 Map[t[#] &, Range[0, 40]] (* A211917 *)
%t A211917 (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y A211917 Cf. A211795.
%K A211917 nonn
%O A211917 0,3
%A A211917 _Clark Kimberling_, Apr 27 2012