25_better.py

import math
import time

def main():
    phi = (1 + pow(5, 0.5)) / 2
    c = math.log10(5) / 2
    logphi = math.log10(phi)
    n = 1
    while True:
        if n*logphi -c >= 999:
            print n
            break
        n = n + 1

if __name__ == "__main__":
    start = time.time()
    main()
    end = time.time()
    print "time: " + str(end-start)