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A376203 a(n) = A376202(2*n-1)/2.

%I A376203 #20 Oct 09 2024 15:25:55
%S A376203 0,1,0,3,0,0,6,0,0,9,6,0,0,0,0,15,0,0,18,12,0,21,0,0,21,0,0,0,18,0,30,
%T A376203 0,0,33,0,0,36,0,0,39,0,0,0,0,0,72,30,0,48,0,0,51,0,0,54,36,0,0,0,0,0,
%U A376203 0,0,63,42,0,108,0,0,69
%N A376203 a(n) = A376202(2*n-1)/2.
%H A376203 Chai Wah Wu, <a href="/A376203/b376203.txt">Table of n, a(n) for n = 1..7814</a>
%o A376203 (Python)
%o A376203 from math import gcd
%o A376203 def A376203(n):
%o A376203     c, m = 0, (n<<1)-1
%o A376203     for x in range(1,m):
%o A376203         if gcd(x,m) == 1:
%o A376203             for y in range(x,m):
%o A376203                 if gcd(y,m)==gcd(z:=x+y,m)==1 and not (w:=z**2-x*y)//gcd(w,x*y*z)%m:
%o A376203                     c += 1
%o A376203     return c>>1 # _Chai Wah Wu_, Oct 06 2024
%Y A376203 Cf. A000086, A087786, A046530, A290731, A376202, A376755, A376756, A376757.
%K A376203 nonn
%O A376203 1,4
%A A376203 _Tom Duff_ and _N. J. A. Sloane_, Oct 06 2024