Here are a couple of unusual jigsaw puzzles. In fact you may not even consider them to be jigsaw puzzles, as they are not cut from a single board of wood. But I think that they can rightly be considered to be tray jigsaw puzzles. They also differ from regular puzzles in that they have multiple correct solutions, in fact so many different solutions that it confounds common sense!

The puzzles are based on the mathematical concept of Pentominoes. Briefly, a Pentomino consists of five connected squares in the same way that a domino consists of two connected squares. There is a lot of information on the Internet on the subject of Pentominoes, and this is a good starting point: en.wikipedia.org/wiki/Pentomino. There are 12 distinct Pentominos, and these puzzles both require you to fit them into a tray.

The first puzzle uses the set of 12 Pentominoes (total area 5 x 12 = 60 units) and they must be fitted into a 6 x 10 tray (also area 60 units). The second puzzle adds a 2 x 2 square to the 12 Pentominos, making 13 pieces with a total area of 64 units, which must be fitted into an 8 x 8 square tray.

The pieces are all cut from 1/4" hardwood, each piece from a different species. The pieces are left in their natural state, not stained, just wiped with tung oil to bring out the color and grain. The basic square unit on which the Pentominoes are based is 3/8" x 3/8". so the tray for the first puzzle measures 2-1/4" x 3-3/4" and for the second 3" x 3". The box for the first puzzle measures 3" x 4-1/2" x 1/2" and for the second 3-3/4" x 3-3/4" x 1/2".

Either puzzle can easily take a hour to find a first solution, yet there are 2339 different solutions to the 6 x 10 puzzle and a whopping 16146 solutions to the 8 x 8 puzzle!

The puzzles are based on the mathematical concept of Pentominoes. Briefly, a Pentomino consists of five connected squares in the same way that a domino consists of two connected squares. There is a lot of information on the Internet on the subject of Pentominoes, and this is a good starting point: en.wikipedia.org/wiki/Pentomino. There are 12 distinct Pentominos, and these puzzles both require you to fit them into a tray.

The first puzzle uses the set of 12 Pentominoes (total area 5 x 12 = 60 units) and they must be fitted into a 6 x 10 tray (also area 60 units). The second puzzle adds a 2 x 2 square to the 12 Pentominos, making 13 pieces with a total area of 64 units, which must be fitted into an 8 x 8 square tray.

The pieces are all cut from 1/4" hardwood, each piece from a different species. The pieces are left in their natural state, not stained, just wiped with tung oil to bring out the color and grain. The basic square unit on which the Pentominoes are based is 3/8" x 3/8". so the tray for the first puzzle measures 2-1/4" x 3-3/4" and for the second 3" x 3". The box for the first puzzle measures 3" x 4-1/2" x 1/2" and for the second 3-3/4" x 3-3/4" x 1/2".

Either puzzle can easily take a hour to find a first solution, yet there are 2339 different solutions to the 6 x 10 puzzle and a whopping 16146 solutions to the 8 x 8 puzzle!

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