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A181787 Number of solutions to n^2 = a^2 + b^2 + c^2 with positive a, b, c. 2
0, 0, 0, 3, 0, 0, 3, 6, 0, 12, 0, 9, 3, 6, 6, 15, 0, 9, 12, 15, 0, 33, 9, 18, 3, 12, 6, 39, 6, 18, 15, 24, 0, 48, 9, 30, 12, 24, 15, 45, 0, 27, 33, 33, 9, 60, 18, 36, 3, 48, 12, 60, 6, 36, 39, 45, 6, 78, 18, 45, 15, 42, 24, 114, 0, 36, 48, 51, 9, 93, 30, 54, 12, 51, 24, 87, 15, 87, 45, 60, 0, 120, 27, 63, 33, 51, 33, 105, 9, 63, 60, 84, 18, 123, 36, 75, 3, 69, 48, 165, 12 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Note that a(n)=0 for n=0 and the n in A094958.

LINKS

Table of n, a(n) for n=0..100.

MATHEMATICA

nn=100; t=Table[0, {nn}]; Do[n=Sqrt[a^2+b^2+c^2]; If[n<=nn && IntegerQ[n], t[[n]]++], {a, nn}, {b, nn}, {c, nn}]; Prepend[t, 0]

CROSSREFS

Cf. A016725, A016727, A181786, A181788.

Sequence in context: A222522 A091921 A037285 * A005082 A050452 A200517

Adjacent sequences:  A181784 A181785 A181786 * A181788 A181789 A181790

KEYWORD

nonn

AUTHOR

T. D. Noe, Nov 12 2010

STATUS

approved

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Last modified May 20 17:23 EDT 2013. Contains 225464 sequences.