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A239680 Number of pairs (x,y) in {0,...,n-1}^2 such that x^2+y^2 divides n. 0
0, 3, 2, 5, 4, 3, 2, 6, 4, 7, 2, 5, 4, 3, 4, 8, 4, 6, 2, 11, 2, 3, 2, 6, 8, 7, 4, 5, 4, 7, 2, 9, 2, 7, 4, 10, 4, 3, 4, 14, 4, 3, 2, 5, 8, 3, 2, 8, 4, 14, 4, 11, 4, 6, 4, 6, 2, 7, 2, 11, 4, 3, 4, 11, 10, 3, 2, 11, 2, 7, 2, 12, 4, 7, 8, 5, 2, 7, 2, 18, 6, 7, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..83.

MATHEMATICA

A[n_] := Sum[If[GCD[a^2 + b^2, n] == a^2 + b^2, 1, 0], {a, 0, n - 1}, {b, 0, n - 1}]; Array[A, 100]

CROSSREFS

Sequence in context: A205850 A204890 A307775 * A128076 A076243 A140061

Adjacent sequences:  A239677 A239678 A239679 * A239681 A239682 A239683

KEYWORD

nonn

AUTHOR

José María Grau Ribas, Mar 23 2014

STATUS

approved

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Last modified August 17 15:35 EDT 2022. Contains 356189 sequences. (Running on oeis4.)