Happy Numbers

Date: Mar 18, 2007

Happy Numbers

fht · Long-term Member

Take a number, find the sum of the squares of all its digits, then do the same to all the digits of the sum, and keep on that process until you either end up with 1 or an infinite loop. In the first case, the number is happy.
FMI, http://en.wikipedia.org/wiki/Happy_number and http://mathworld.wolfram.com/HappyNumber.html
Best Wishes

bradp · Senior Member

sam is beating me to the punch

-- Edited by bradp at 18:57, 2007-03-18

useless · Long-term Member

I thought unhappy numbers go to 4 rather than 1. Is that true?

Zack

bradp · Senior Member

from wikipedia article:
"

If n is not happy, then its sequence does not go to 1. What happens instead is that it ends up in the cycle

4, 16, 37, 58, 89, 145, 42, 20, 4, ...

"