def is_lychrel(n, i=0): if i > 50: return True reverse = int(str(n)[::-1]) s = n + reverse if euler.is_palindrome(s): return False else: return is_lychrel(s, i+1)
"""
Find the sum of all numbers, less than one million, which are palindromic in base 10 and base 2.
"""
from lib import euler
# seems easy enough...
def to_binary(n):
s = ''
if n == 0: return '0'
while n:
s += '1' if n % 2 else '0'
n = n >> 1
return s[::-1]
palindromes = []
for i in xrange(10**6):
if euler.is_palindrome(i) and euler.is_palindrome(to_binary(i)):
palindromes += [i]
print sum(palindromes)
#!/usr/bin/env python
"""Find the largest palindrome made from the product of two 3-digit numbers."""
from lib import euler
largest = 0
for i in xrange(100, 1000):
for j in xrange(100, 1000):
product = i*j
if euler.is_palindrome(product) and product > largest:
largest = product
print largest