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A211633 Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2>2x^2+2y^2. 2

%I #5 Dec 04 2016 19:46:27

%S 0,0,0,8,32,80,160,264,416,624,864,1176,1552,2000,2528,3144,3856,4640,

%T 5552,6584,7712,8960,10352,11880,13520,15328,17296,19416,21712,24176,

%U 26832,29640,32672,35904,39312,42968,46816,50896,55184,59736

%N Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2>2x^2+2y^2.

%C For a guide to related sequences, see A211422.

%t t = Compile[{{u, _Integer}},

%t Module[{s = 0}, (Do[If[w^2 > 2 x^2 + 2 y^2,

%t s = s + 1], {w, #}, {x, #}, {y, #}] &[

%t Flatten[{Reverse[-#], #} &[Range[1, u]]]]; s)]];

%t Map[t[#] &, Range[0, 50]] (* A211633 *)

%t %/8 (* integers *)

%t (* _Peter J. C. Moses_, Apr 13 2012 *)

%Y Cf. A211422.

%K nonn

%O 0,4

%A _Clark Kimberling_, Apr 17 2012

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Last modified August 24 15:58 EDT 2024. Contains 375417 sequences. (Running on oeis4.)