Euler #73

from math import gcd as bltin_gcd


def coprime(a, b):
    return bltin_gcd(a, b) == 1

answer = 0
for a in range(2, 12001):
    print(a)
    index = int(a/3)
    for b in range(index, int(a/2)+1):
        if b/a <= 1/3:
            continue
        if b/a >= 1/2:
            break
        if coprime(a, b):
            answer += 1
print(answer)