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 A281877 Numbers that are a primitive sum of two squares in more than 2 ways. 3
 1105, 1885, 2210, 2405, 2465, 2665, 3145, 3445, 3485, 3770, 3965, 4505, 4745, 4810, 4930, 5185, 5330, 5365, 5525, 5785, 5945, 6205, 6290, 6305, 6409, 6565, 6890, 6970, 7085, 7345, 7565, 7585, 7685, 7930, 8177, 8245, 8585, 8845, 8905, 9010, 9061, 9265, 9425, 9490, 9605, 9685, 9805 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS "Primitive" means that x and y are coprime in the representations x^2+y^2. LINKS Robert Israel, Table of n, a(n) for n = 1..10000 MAPLE N:= 10^4: # to get all terms <= N V:= Vector(N): for a from 1 to floor(sqrt(N)) do   for b from 1 to min(a, floor(sqrt(N-a^2))) do     if igcd(a, b) > 1 then next fi;     r:= a^2 + b^2;     V[r]:= V[r]+1; od od: select(n -> V[n] > 2, [\$1..N]); # Robert Israel, Feb 07 2017 CROSSREFS Cf. A224450 (exactly 1 way), A224770 (exactly 2 ways), A008784, A097102. Sequence in context: A025305 A052155 A097102 * A159781 A264498 A102924 Adjacent sequences:  A281874 A281875 A281876 * A281878 A281879 A281880 KEYWORD nonn AUTHOR R. J. Mathar, Feb 01 2017 STATUS approved

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Last modified August 13 05:41 EDT 2020. Contains 336442 sequences. (Running on oeis4.)