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A263425
Number of tilings of an 2n X 2n square using tetrominoes of any shape.
1
1, 1, 117, 178939, 19077209438, 72713560548906621
OFFSET
0,3
LINKS
S. Butler, J. Ekstrand, S. Osborne, TETRIS Tiling, AMS Spring Central Sectional, Iowa State University, April 27-28 2013
Wikipedia, Tetromino
FORMULA
a(n) = A230031(2n,2n).
CROSSREFS
Bisection (even part) of main diagonal of A230031.
Cf. A004003.
Sequence in context: A079196 A113798 A151593 * A066923 A039556 A356729
KEYWORD
nonn,more
AUTHOR
Alois P. Heinz, Oct 17 2015
STATUS
approved