by SCLT » Thu Jul 25, 2019 1:00 pm
Reviving this old thread... I had been independently researching NC puzzles over the last week or so (with 1 and 9 _not_ being considered consecutive). I have some results which confirm those appearing in this thread, and some new results about minimal puzzles.
- There are 5,287,048 valid NC grids
- There are 330,845 non-isomorphic valid NC grids
- There are 809 non-isomorphic NC grids with at least one symmetry
- There are no 3-clue NC puzzles
- There are 609,032 4-clue NC puzzles
- There are 38,065 non-isomorphic 4-clue NC puzzles
- There is exactly one 4-clue symmetric NC puzzle: .................................3...4.....6...7.................................