Determine the smallest value of a positive integer N such that the digit immediately preceding the decimal point in the expansion of √N is 2 and the three digits immediately following the decimal point is 015 (in this order)

*** Extra Challenge: A non-computer program assisted method.

(In reply to confirmed solution by Charlie)

Yes I confirmed my solution after posing in that way as well.
Is 2.015 just an easy number?
Is my method ever more efficient than just trying the first few potential numbers?

Posted by Jer on 2015-08-14 11:28:21