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Summing inverses II (Posted on 2012-03-16) Difficulty: 3 of 5
The sum of the reciprocal of the square root of all the positive integers up to n is denoted by F(n), that is:

F(n) = 1+1/√2 + 1/√3 +...+ 1/√n

Determine the maximum value of n such that the integer part of the base ten expansion of F(n) DOES NOT exceed 2012.

*** For an extra challenge, solve this puzzle without using a computer program.

No Solution Yet Submitted by K Sengupta    
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Now I've seen how it's done... | Comment 8 of 12 |

 x=INT((2012+y)^2*1/4). If y=0, then x=1012036

 If y=(log(2012))^(1/2) then x= 1014812. But I suspect y is more complex than this.


  Posted by broll on 2012-03-17 02:11:19
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