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%I A212741 #14 Jun 13 2015 00:54:14
%S A212741 1,15,79,239,593,1199,2239,3759,6049,9119,13391,18815,25969,34719,
%T A212741 45823,59039,75329,94319,117199,143439,174481,209615,250559,296399,
%U A212741 349153,407679,474319,547679,630449,720959,822271,932415,1054849
%N A212741 Number of (w,x,y,z) with all terms in {0,...,n} and max{w,x,y,z}>=2*min{w,x,y,z}.
%C A212741 Also the number of (w,x,y,z) with all terms in {0,...,n} and at least one term <= range{w,x,y,z}.
%C A212741 Every term is odd.
%C A212741 a(n)+A212740(n)=n^4.
%C A212741 For a guide to related sequences, see A211795.
%H A212741 <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (2,2,-6,0,6,-2,-2,1)
%F A212741 a(n) = 2*a(n-1)+2*a(n-2)-6*a(n-3)+6*a(n-5)-2*a(n-6)-2*a(n-7)+a(n-8).
%F A212741 G.f.: ( -1-13*x-47*x^2-57*x^3-47*x^4-3*x^5-x^6+x^7 ) / ( (1+x)^3*(x-1)^5 ).
%t A212741 t = Compile[{{n, _Integer}}, Module[{s = 0},
%t A212741 (Do[If[Max[w, x, y, z] >= 2 Min[w, x, y, z], s = s + 1],
%t A212741 {w, 0, n}, {x, 0, n}, {y, 0, n}, {z, 0, n}]; s)]];
%t A212741 Map[t[#] &, Range[0, 40]]   (* A212741 *)
%Y A212741 Cf. A211795, A212743.
%K A212741 nonn,easy
%O A212741 0,2
%A A212741 _Clark Kimberling_, May 26 2012

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