speakable_numbers.py

even_letters = "bcdfghlmnprstwx"
odd_letters = "aeiou"

def format_uid_digit (n, level):
    if n != 0:
        letters = odd_letters if (level & 1) else even_letters
        base = len(letters)
        s = format_uid_digit(n / base, level + 1)
        return s + letters[(n % base)]
    return ""

def format_uid (uid):
    return format_uid_digit(uid, 0)

import random
for i in range(100):
    k = random.randrange(1000000,2000000)
    print k, format_uid(k)