A220055 Number of tilings of a 5 X n rectangle using right trominoes and 1 X 1 tiles.

1, 1, 87, 849, 16839, 249651, 4134881, 65564239, 1057354073, 16939662301, 272086395449, 4365892578855, 70082433262847, 1124809701807527, 18054055051423891, 289774657566172859, 4651038841674376909, 74651407535212480809, 1198192596525147061411

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..300

Formula

G.f.: see Maple program.

Maple

gf:= (20*x^12 +88*x^11 -162*x^10 +26*x^9 +506*x^8 +453*x^7 -605*x^6 -300*x^5 -12*x^4 +47*x^3 +63*x^2 +6*x -1) /
(76*x^14 -152*x^13 -212*x^12 -64*x^11 +1180*x^10 -1738*x^9 -3069*x^8 +308*x^7 +5229*x^6 -756*x^5 -1701*x^4 +144*x^3 +143*x^2 +7*x -1):
a:= n-> coeff (series (gf, x, n+1), x, n):
seq(a(n), n=0..30);

Crossrefs

Column k=5 of A220054.

Sequence in context: A109601 A297723 A061625 * A281806 A128956 A283952

Adjacent sequences: A220052 A220053 A220054 * A220056 A220057 A220058

Keyword

nonn

Author

Alois P. Heinz, Dec 03 2012

Status

approved