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a) is easy, b) is not (Posted on 2011-02-18) Difficulty: 3 of 5
1, 2, 4, 8, 1, 3, 6, 1 ... is a non-cyclic series where a(n) represents the leading digit of 2^n.

a) How many ones are there within the first 3000 members?
b) Same question for a digit d, other than digit one.

No Solution Yet Submitted by Ady TZIDON    
Rating: 3.0000 (2 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
My error - why we disagree on part 1 Comment 8 of 8 |
Ady's sequence starts at n=0 so when he requests we consider the first 3000 members the last is actually the leading digit of 2^2999.  a(3000)=6

So the answer really is 903.

  Posted by Jer on 2011-02-19 17:57:58
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