def expand_x_1(n):
# This version uses a generator and thus less computations
    c =1
    for i in range(n//2+1):
        c = c*(n-i)//(i+1)
        yield c

def aks(p):
    if p==2:
        return True

    for i in expand_x_1(p):
        if i % p:
# we stop without computing all possible solutions
            return False
    return True