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A281877 Numbers that are a primitive sum of two squares in more than 2 ways.

%I A281877 #7 Feb 07 2017 10:46:59
%S A281877 1105,1885,2210,2405,2465,2665,3145,3445,3485,3770,3965,4505,4745,
%T A281877 4810,4930,5185,5330,5365,5525,5785,5945,6205,6290,6305,6409,6565,
%U A281877 6890,6970,7085,7345,7565,7585,7685,7930,8177,8245,8585,8845,8905,9010,9061,9265,9425,9490,9605,9685,9805
%N A281877 Numbers that are a primitive sum of two squares in more than 2 ways.
%C A281877 "Primitive" means that x and y are coprime in the representations x^2+y^2.
%H A281877 Robert Israel, <a href="/A281877/b281877.txt">Table of n, a(n) for n = 1..10000</a>
%p A281877 N:= 10^4: # to get all terms <= N
%p A281877 V:= Vector(N):
%p A281877 for a from 1 to floor(sqrt(N)) do
%p A281877   for b from 1 to min(a, floor(sqrt(N-a^2))) do
%p A281877     if igcd(a,b) > 1 then next fi;
%p A281877     r:= a^2 + b^2;
%p A281877     V[r]:= V[r]+1;
%p A281877 od od:
%p A281877 select(n -> V[n] > 2, [$1..N]); # _Robert Israel_, Feb 07 2017
%Y A281877 Cf. A224450 (exactly 1 way), A224770 (exactly 2 ways), A008784, A097102.
%K A281877 nonn
%O A281877 1,1
%A A281877 _R. J. Mathar_, Feb 01 2017