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A211918 Number of (w,x,y,z) with all terms in {1,...,n} and w*x>3*y*z.

%I A211918 #7 Dec 04 2016 19:46:28
%S A211918 0,0,1,6,32,100,219,441,797,1312,2061,3107,4451,6248,8526,11336,14823,
%T A211918 19090,24122,30164,37253,45501,55091,66154,78663,92979,109170,127281,
%U A211918 147629,170403,195536,223509,254329,288192,325385,366061
%N A211918 Number of (w,x,y,z) with all terms in {1,...,n} and w*x>3*y*z.
%C A211918 a(n)+A211912(n)=n^4.
%C A211918 See A211795 for a guide to related sequences.
%t A211918 t = Compile[{{n, _Integer}}, Module[{s = 0},
%t A211918 (Do[If[w*x > 3 y*z, s = s + 1],
%t A211918 {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t A211918 Map[t[#] &, Range[0, 40]] (* A211918 *)
%t A211918 (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y A211918 Cf. A211795.
%K A211918 nonn
%O A211918 0,4
%A A211918 _Clark Kimberling_, Apr 27 2012