perplexus.info :: Just Math : Repunit Rigor II

Repunit Rigor II (Posted on 2013-10-01)

sod(n) denotes the sum of the digits of a base ten positive integer n, and:
R_t = 11...11 (the digit 1 repeated precisely t times.)

Determine the values of t for which:

sod(R_t²) = (sod(R_t))²

No Solution Yet Submitted by K Sengupta

Rating: 5.0000 (1 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)

Answers

Comment 3 of 3 |

1, 2, 3, 4, 5, 6, 7, 8, 9

Posted by Math Man on 2013-10-05 23:45:50

Please log in:

Login:
Password:
Remember me:

Sign up! \| Forgot password

Search:

Search body:

Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (0)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:


perplexus dot info