OFFSET
1,4
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..7814
PROG
(Python)
from math import gcd
def A376203(n):
c, m = 0, (n<<1)-1
for x in range(1, m):
if gcd(x, m) == 1:
for y in range(x, m):
if gcd(y, m)==gcd(z:=x+y, m)==1 and not (w:=z**2-x*y)//gcd(w, x*y*z)%m:
c += 1
return c>>1 # Chai Wah Wu, Oct 06 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Tom Duff and N. J. A. Sloane, Oct 06 2024
STATUS
approved