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Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2>x^2+y^2.
4

%I #11 Dec 04 2016 19:46:27

%S 0,0,1,5,13,26,48,78,119,173,240,323,421,538,677,837,1020,1226,1460,

%T 1723,2015,2337,2694,3084,3508,3969,4471,5016,5601,6227,6900,7619,

%U 8389,9208,10078,11004,11981,13015,14105,15258,16472,17744,19083,20487,21962,23505

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

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

%H Alois P. Heinz, <a href="/A211637/b211637.txt">Table of n, a(n) for n = 0..1000</a>

%p b:= proc(n) option remember; 1+floor(sqrt(n)) end:

%p a:= proc(n) local c, x, y, w;

%p c:= 0;

%p for x to n do

%p for y from x to n do

%p w:= b(x^2+y^2);

%p if w>n then break fi;

%p c:= c+ (n-w+1)*`if`(x=y, 1, 2)

%p od

%p od: c

%p end:

%p seq (a(n), n=0..50); # _Alois P. Heinz_, May 10 2012

%t t = Compile[{{n, _Integer}}, Module[{s = 0},

%t (Do[If[w^2 > x^2 + y^2, s = s + 1],

%t {w, 1, #}, {x, 1, #}, {y, 1, #}] &[n]; s)]];

%t Map[t[#] &, Range[0, 50]] (* A211637 *)

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

%Y Cf. A211422.

%K nonn

%O 0,4

%A _Clark Kimberling_, Apr 18 2012