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%I #8 Sep 21 2013 16:11:38
%S 1,1,0,1,1,0,1,1,0,1,1,0,0,1,0,1,2,0,1,0,0,2,1,0,1,1,0,1,1,0,0,1,0,0,
%T 1,0,2,1,0,1,0,0,1,1,0,1,2,0,1,1,0,2,0,0,0,2,0,1,1,0,1,0,0,0,1,0,2,1,
%U 0,1,1,0,1,1,0
%N Number of primitive positive solutions to 8n+2=x^2+y^2.
%H R. J. Mathar, <a href="/A106602/b106602.txt">Table of n, a(n) for n = 0..1000</a>
%e a(16)=2 because we have 130=11^2+3^2=9^2+7^2. a(2)=0 because although 18=3^2+3^2, these components are not mutually prime.
%p A106602 := proc(n)
%p local a,x,y,fourn;
%p fourn := 8*n+2 ;
%p a := 0 ;
%p for x from 1 do
%p if x^2 >= fourn then
%p return a;
%p else
%p y := fourn-x^2 ;
%p if issqr(y) then
%p y := sqrt(y) ;
%p if y <= x and igcd(x,y) = 1 then
%p a := a+1 ;
%p end if;
%p end if;
%p end if:
%p end do:
%p end proc: # _R. J. Mathar_, Sep 21 2013
%Y Cf. A106594.
%K easy,nonn
%O 0,17
%A _Colin Mallows_, May 10 2005
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