How many solutions to the 16 dot puzzle are there?
Posted on Nov 29, 2008 under puzzle |You know this old puzzle, a 4×4 grid of dots that you must connect with 6 straight lines without lifting your pen off the paper. I found one solution myself, and two different ones on the internet (one here on answers). Does anyone know how many different solutions there are?
16
By xwdguy on Nov 29, 2008 | Reply
My favorite solution is the one where the starting and ending place are the same. No endpoints are on the dots (or even within the 4×4 grid area). If we call the points
1a 1b 1c 1d
2a 2b 2c 2d
3a 3b 3c 3d
4a 4b 4c 4d
then line 1 sweeps thru 1a-4d diagonal,
next goes thru 3d + 1c, next thru 1b + 3a, next
thru 4a-1d diagonal, next 2d + 4c, next 4b + 2a
and connecting to start of first line.
I'm sure there are plenty of ways to do this omitting
the "start and end at the same place".
References :
Puzzle person
By stealtip on Nov 29, 2008 | Reply
16
References :