A219871 Number of tilings of an 8 X n rectangle using dominoes and straight (3 X 1) trominoes.

1, 4, 123, 5233, 161800, 6155230, 223026907, 8061851335, 295743829064, 10750194262698, 392127322268846, 14301080443962397, 521186161714401053, 19005127884701974465, 692863015545590519355, 25260000472133325186613, 920954865421382858310101

Offset: 0

Author

Alois P. Heinz, Nov 30 2012

Keywords

• nonn

Examples

			a(1) = 4, because there are 4 tilings of an 8 X 1 rectangle using dominoes and straight (3 X 1) trominoes:
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Links

• Alois P. Heinz, Table of n, a(n) for n = 0..200

Crossrefs

Column k=8 of A219866.