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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
0, 0, 0, 3, 3, 3, 6, 12, 12, 24, 24, 33, 36, 42, 48, 63, 63, 72, 84, 99, 99, 132, 141, 159, 162, 174, 180, 219, 225, 243, 258, 282, 282, 330, 339, 369, 381, 405, 420, 465, 465, 492, 525, 558, 567, 627, 645, 681, 684, 732, 744, 804, 810, 846, 885, 930 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

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

LINKS

Table of n, a(n) for n=0..55.

MATHEMATICA

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

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

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

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

%/3  (* integers *)

(* Peter J. C. Moses, Apr 13 2012 *)

CROSSREFS

Cf. A211795.

Sequence in context: A113920 A081848 A079988 * A061021 A126608 A088195

Adjacent sequences:  A212088 A212089 A212090 * A212092 A212093 A212094

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 02 2012

STATUS

approved

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Last modified September 24 08:44 EDT 2020. Contains 337317 sequences. (Running on oeis4.)