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A360256
Number of ways to tile an n X n square using rectangles with distinct height X width dimensions.
5
1, 1, 33, 513, 14409, 693025, 50447161
OFFSET
1,3
COMMENTS
All possible tilings are counted, including those identical by symmetry. Note that distinct height X width dimensions means that, for example, a 1 X 3 rectangle can be used twice, once in a horizonal (1 X 3) and once in a vertical (3 X 1) direction.
EXAMPLE
a(1) = 1 as the only way to tile a 1 X 1 square is with a square with dimensions 1 X 1.
a(2) = 1 as the only way to tile a 2 X 2 square is with a square with dimensions 2 X 2.
a(3) = 33. The possible tilings, excluding those equivalent by symmetry, are:
.
+---+---+---+ +---+---+---+ +---+---+---+ +---+---+---+ +---+---+---+
| | | | | | | | | | | | | |
+---+---+---+ +---+---+---+ +---+---+ + +---+---+---+ +---+---+---+
| | | | | | | | | | | | |
+ + + + + + + + + + + + +
| | | | | | | | | | | | |
+---+---+---+ +---+---+---+ +---+---+---+ +---+---+---+ +---+---+---+
.
The first tiling can occur in 4 different ways, the second in 8 different ways, the third in 8 different ways, the fourth in 4 different ways and the fifth in 8 different ways. There is also the single 3 X 3 rectangle. This gives 33 ways in total.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Scott R. Shannon, Feb 17 2023
STATUS
approved