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The infinite sequence is defined as follows:
a1=1
for n ≥ 1, a2n= an+1
a2n+1=1/ a2n

Prove that every positive rational number occurs in the sequence exactly once.
(No Solution Yet, 0 Comments) Submitted on 2016-08-26 by Ady TZIDON   
Difficulty: 2 of 5 Bonus: Odd Sum (in Just Math) Rating: 3.90
Prove that the sum of consecutive odd numbers beginning at 1 (eg 1, 3, 5, ..) always adds up to a perfect square
(Solution Posted, 17 Comments) Submitted on 2002-08-08 by Cheradenine   
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Posted on 2016-08-18 by Brian Smith (No Solution Yet, 3 Comments)

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