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A211787 Number of (w,x,y,z) with all terms in {1,...,n} and w*x<=2*y*z.

%I A211787 #10 Dec 04 2016 19:46:28
%S A211787 0,1,15,66,201,469,958,1735,2937,4656,7050,10242,14461,19813,26569,
%T A211787 34904,45086,57293,71898,89050,109201,132534,159424,190167,225296,
%U A211787 264966,309685,359823,415889,478142,547302,623514,707593,799821
%N A211787 Number of (w,x,y,z) with all terms in {1,...,n} and w*x<=2*y*z.
%C A211787 a(n)+A211797(n)=n^4.
%C A211787 See A211795 for a guide to related sequences.
%H A211787 Bo Gyu Jeong, <a href="/A211787/b211787.txt">Table of n, a(n) for n = 0..200</a>
%t A211787 t = Compile[{{n, _Integer}}, Module[{s = 0},
%t A211787     (Do[If[w*x <= 2 y*z, s = s + 1],
%t A211787     {w, 1, #}, {x, 1, #}, {y, 1, #},
%t A211787       {z, 1, #}] &[n]; s)]];
%t A211787 Map[t[#] &, Range[0, 40]] (* A211787 *)
%t A211787 (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y A211787 Cf. A211795.
%K A211787 nonn
%O A211787 0,3
%A A211787 _Clark Kimberling_, Apr 27 2012