Determine all possible positive base ten repdigit(s) N, such that the sum of the digits of N² is equal to 37.

(In reply to computer solution by Charlie)

A minor problem with the solution method.  n^2 could have more than 37 digits, if some of them are zero.  Most of the non-zero ones would need to be 1, so this isn't a practical objection, but I think the program should check for repunits with more than 19 digits, just in case. 

Posted by Steve Herman on 2009-06-04 15:21:11