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A239680 Number of pairs (x,y) in {0,...,n-1}^2 such that x^2+y^2 divides n. 0

%I

%S 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,

%T 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,

%U 3,2,11,2,7,2,12,4,7,8,5,2,7,2,18,6,7,2

%N Number of pairs (x,y) in {0,...,n-1}^2 such that x^2+y^2 divides n.

%t 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]

%K nonn

%O 1,2

%A _José María Grau Ribas_, Mar 23 2014

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Last modified September 27 04:03 EDT 2022. Contains 357052 sequences. (Running on oeis4.)