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A212091 Number of (w,x,y,z) with all terms in {1,...,n} and w^2=x^2+y^2+z^2. 3

%I #9 Jun 26 2022 09:17:21

%S 0,0,0,3,3,3,6,12,12,24,24,33,36,42,48,63,63,72,84,99,99,132,141,159,

%T 162,174,180,219,225,243,258,282,282,330,339,369,381,405,420,465,465,

%U 492,525,558,567,627,645,681,684,732,744,804,810,846,885,930

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

%C Every term is divisible by 3. For a guide to related sequences, see A211795.

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

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

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

%t Map[t[#] &, Range[0, 50]] (* A212091 *)

%t %/3 (* integers *)

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

%Y Cf. A211795.

%Y Partial sums of A181787.

%K nonn

%O 0,4

%A _Clark Kimberling_, May 02 2012

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Last modified April 23 08:29 EDT 2024. Contains 371905 sequences. (Running on oeis4.)