Double End Of

pi = ''

with open('/path/to/pi.txt') as the_file: pi = the_file.read()      # This file should start without "3." in the front

for n in range(1, 7):
    for i in range(0, len(pi)):
        end_of = i + n
        num = pi[i:end_of]
        d = int(num) * 2

        if d == end_of:
            print(num)

"""
Pi: 5, 19, 94, 619, 61512
Phi:    1, 3, 8, 331, 519, 1129, 44905, 49229, 66762
e:      1, 2, 636, 637, 190853
em: 2, 8, 12, 8403, 08403, 46466, 51309, 71069, 77172
2Pi:    92, 7084, 7212, 13485, 45163, 92165
"""