A353964 Number of tilings of a 2 X n rectangle using 2 X 2 and 1 X 1 tiles and right trominoes.

1, 1, 6, 13, 45, 122, 373, 1073, 3182, 9293, 27349, 80178, 235509, 691097, 2028998, 5955501, 17482685, 51318186, 150642613, 442198913, 1298048350, 3810328141, 11184967717, 32832705122, 96378199989, 282911661033, 830468071222, 2437782776365, 7155946454541

Offset: 0

Author

Gerhard Kirchner, May 13 2022

Keywords

• nonn
• easy

Comments

For tiling algorithm see A351322.

Examples

			a(3)=13, see example 3 X 2, A353965.
		

Links

• Index entries for linear recurrences with constant coefficients, signature (1,5,2).

Crossrefs

Cf. A351322, A352589, A353963, A353965.

Programs

Maxima

See A352589.

Formula

G.f.: 1 / (1 - x - 5*x^2 - 2*x^3).

a(n) = a(n-1) + 5*a(n-2) + 2*a(n-3).