RosettaCodeData/Task/Chowla-numbers/Python/chowla-numbers-2.py

35 lines
751 B
Python

from numba import jit
# https://docs.sympy.org/latest/modules/ntheory.html#sympy.ntheory.factor_.divisors
from sympy import divisors
@jit
def chowla(n):
return 0 if n < 2 else sum(divisors(n, generator=True)) - 1 -n
@jit
def is_prime(n):
return chowla(n) == 0
@jit
def primes_to(n):
acc = 0
for i in range(2, n):
if chowla(i) == 0:
acc += 1
return acc
@jit
def _perfect_between(n, m):
for i in range(n, m):
if i > 1 and chowla(i) == i - 1:
yield i
def perfect_between(n, m):
c = 0
print(f"\nPerfect numbers between [{n:_}, {m:_})")
for i in _perfect_between(n, m):
print(f" {i:_}")
c += 1
print(f"Found {c} Perfect numbers between [{n:_}, {m:_})")