All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars
 perplexus dot info

 Leonardo's game (Posted on 2014-06-27)
Two players start with a pile of stones.
1st player takes any number of stones from the pile, but not all of them.
Then the players alternate, taking up to twice as many stones
as their opponent just took.
The player taking the last stone (or stones) is the winner.

Question: If you and your friend start with 100 stones, what is the smallest amount of stones you should take on your 1st turn, and how will you proceed to win the game?

 No Solution Yet Submitted by Ady TZIDON No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
 Fibonacci Comment 3 of 3 |

Interestingly, and surely not coincidentally, each of the Fibonacci terms 3, 5, 8, 13, 21, 34, 55, and 89 are "safe spots" where you can leave your opponent en route to a victory.  I can't yet come up with a simple way to explain why this is the case, though.

Even more specifically, while the Fibonacci terms are not the only "safe spots", they are the only spots from which the only winning move is to take ALL the remaining stones.

Edited on June 30, 2014, 4:04 pm
 Posted by tomarken on 2014-06-30 15:39:39

 Search: Search body:
Forums (0)
Random Problem
Site Statistics
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox: