Пример #1
0
def trunc(n):
  c = n
  while c>10:
    c = c % 10**(int(log10(c)))
    n = n//10
    if not isPrime(c) or not isPrime(n): return False 
  return True
Пример #2
0
def phi(n):
#	return len([i for i in range(1,n) if mcd(i,n)==1])
	if isPrime(n):
		return n-1
	else:
		prod = float(n)
		factores = factorization(n)
		for i in factores:
			prod = prod * (1 - (1/float(i)))
		return int(prod)
Пример #3
0
"""
The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
Find the sum of all the primes below two million.
"""

import reto7

if __name__ == "__main__":
    print sum([long(i) for i in range(2 * (10 ** 6)) if reto7.isPrime(i) and i > 1])
Пример #4
0
#!/usr/bin/env python
"""
The prime factors of 13195 are 5, 7, 13 and 29.

What is the largest prime factor of the number 600851475143 ?
"""
import math

import reto7

def esPrimo(n):
	for i in range(n):
		if i!=0 and i!=1 and i!=2:
			if n%i==0:
				return False
	return True

if __name__ == "__main__":
	num = 600851475143L
	#lista = [long(i) for i in reversed(long(num)) if i!=0 and num%i==0 and esPrimo(i)]
	for i in reversed(range(long(math.sqrt(num)))):
		if num % i == 0 and reto7.isPrime(i):
			lista = i
			break

	print lista