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A211797 Number of 4-tuples (w,x,y,z) with all terms in {1,...,n} and w*x>2*y*z.

%I A211797 #11 Dec 04 2016 19:46:28
%S A211797 0,0,1,15,55,156,338,666,1159,1905,2950,4399,6275,8748,11847,15721,
%T A211797 20450,26228,33078,41271,50799,61947,74832,89674,106480,125659,147291,
%U A211797 171618,198767,229139,262698,300007,340983,386100,435544,489598
%N A211797 Number of 4-tuples (w,x,y,z) with all terms in {1,...,n} and w*x>2*y*z.
%C A211797 a(n)+A211787(n)=n^4.
%C A211797 See A211795 for a guide to related sequences.
%H A211797 Bo Gyu Jeong, <a href="/A211797/b211797.txt">Table of n, a(n) for n = 0..200</a>
%t A211797 t = Compile[{{n, _Integer}}, Module[{s = 0},
%t A211797     (Do[If[w*x > 2 y*z, s = s + 1], {w, 1, #},
%t A211797       {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t A211797 Map[t[#] &, Range[0, 40]] (* A211797 *)
%t A211797 (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y A211797 Cf. A211795.
%K A211797 nonn
%O A211797 0,4
%A A211797 _Clark Kimberling_, Apr 27 2012