Factorial primes: Difference between revisions

TakesThis takes about 32 seconds to find the first 33 factorial primes on my machine (Ryzen 5 1500X).

i: intfact = 1

n:for inti =in count(1):

while True: yield fact

yieldfact n*= i

for in, nfact in enumerate(factorials()):

if gmpy2.is_prime(nfact - 1):

yield (in, nfact - 1, "-")

if gmpy2.is_prime(nfact + 1):

yield (in, nfact + 1, "+")

def mainprint_factorial_primes(nlimit=10) -> None:

print(f"First {nlimit} factorial primes.")

for in, factorial_primefact_prime, op in islice(factorial_primes(), 1, nlimit + 1):

s = str(factorial_primefact_prime)

print(f"{in}! {op} 1 = {s}")

mainprint_factorial_primes(int(sys.argv[1]) if len(sys.argv) > 1 else 10)