Are you happy or unhappy? The Last PartAlgebra Level pending
The final and last part of this problem:
How many happy numbers are less than 10,000?
Read the previous parts to find the question. You can go to the "My Favorites" Set to find it.
OR go to this link: https://brilliant.org/profile/jonathan-ydncjm/sets/are-you-happy-or-unhappy/