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Integers only (Posted on 2014-03-31) Difficulty: 3 of 5
What is the smallest pair (a1,a2) of integers (a1, less than a2) to provide a list of 24 integers using
a recurrent function a(n)=(a(n-1)+a(n-2))/2?

See The Solution Submitted by Ady TZIDON    
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Solution re: Some questions / Possible solution(s) | Comment 2 of 7 |
(In reply to Some questions / Possible solution(s) by tomarken)

The key is that both starting numbers be divisible by 2^22.  So you can just use a1=0 and a2=2^22.
a1=0
a2=2^22 = 4194304
a3=2^21
a4=2^21 + 2^20
a5=2^21 + 2^19
a6=2^21 + 2^19 + 2^18
...
a23=2^21 + 2^19 + 2^17 + ... + 2^1
a24=2^21 + 2^19 + 2^17 + ... + 2^1 + 2^0 = 2796203

Edited on March 31, 2014, 3:05 pm
  Posted by Jer on 2014-03-31 14:56:35

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