# Eulers Totient function finds the number of relative primes of a number n from 1 to n
def totient(n: int) -> list:
is_prime = [True for i in range(n + 1)]
totients = [i - 1 for i in range(n + 1)]
primes = []
for i in range(2, n + 1):
if is_prime[i]:
primes.append(i)
for j in range(0, len(primes)):
if i * primes[j] >= n:
break
is_prime[i * primes[j]] = False
if i % primes[j] == 0:
totients[i * primes[j]] = totients[i] * primes[j]
break
totients[i * primes[j]] = totients[i] * (primes[j] - 1)
return totients
def test_totient() -> None:
"""
>>> n = 10
>>> totient_calculation = totient(n)
>>> for i in range(1, n):
... print(f"{i} has {totient_calculation[i]} relative primes.")
1 has 0 relative primes.
2 has 1 relative primes.
3 has 2 relative primes.
4 has 2 relative primes.
5 has 4 relative primes.
6 has 2 relative primes.
7 has 6 relative primes.
8 has 4 relative primes.
9 has 6 relative primes.
"""
pass
if __name__ == "__main__":
import doctest
doctest.testmod()