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        riddles >> hard >> THE LAST 1000 DIGITS: Puzzle Extension
        
(Message started by: K Sengupta on May 27^th, 2006, 10:38pm)

Title: THE LAST 1000 DIGITS: Puzzle Extension
Post by K Sengupta on May 27^th, 2006, 10:38pm

This refers to “THE LAST 1000 DIGITS” ( http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_hard;action=display;num=1133282207) which was contributed by pcbouhid.

How can the solution to the above problem be modified to determine the last 10,000 digits of the number

M = 1 + 40 + 40^2 + 40^3 + …………+ 40^9999?

Title: Re: THE LAST 1000 DIGITS: Puzzle Extension
Post by JocK on May 28^th, 2006, 2:22am

[hideb]
M = (40^10,000 - 1)/(40 - 1)

M = ...999999999999999999 * 0.025641025641...

So, the last 1000 digits are just a repitition of the string "025641".
[/hideb]