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A019439 Number of ways of tiling a 2 X n rectangle with dominoes and triominoes. 1
1, 2, 6, 17, 43, 108, 280, 727, 1875, 4832, 12470, 32191, 83075, 214372, 553214, 1427673, 3684333, 9507936, 24536616, 63320419, 163407771, 421697922, 1088253936, 2808400703, 7247494517, 18703234038, 48266468208, 124558777387, 321442392689, 829529751892 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The old entry with this sequence number was a duplicate of A007737.

REFERENCES

Jaime Rangel-Mondragon, Polyominoes and Related Families, The Mathematica Journal, 9:3 (2005), 609-640.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..750

Index entries for linear recurrences with constant coefficients, signature (2, 0, 3, 2, 1, -1).

FORMULA

G.f.: -(x^3+x-1)/(x^6-x^5-2*x^4-3*x^3-2*x+1). - Alois P. Heinz, Sep 24 2009

MAPLE

a:= n-> (Matrix([[1, 1, 0, 0, 1, 1]]). Matrix (6, (i, j)-> if i=j-1 then 1 elif j=1 then [2, 0, 3, 2, 1, -1][i] else 0 fi)^n)[1, 2]: seq (a(n), n=1..30); # Alois P. Heinz, Sep 24 2009

MATHEMATICA

LinearRecurrence[{2, 0, 3, 2, 1, -1}, {1, 1, 2, 6, 17, 43}, 40] // Rest (* Jean-Fran├žois Alcover, Feb 18 2016 *)

CROSSREFS

Sequence in context: A229732 A014833 A130104 * A018024 A190159 A000996

Adjacent sequences:  A019436 A019437 A019438 * A019440 A019441 A019442

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Oct 04 2008

EXTENSIONS

More terms from Alois P. Heinz, Sep 24 2009

STATUS

approved

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Last modified March 19 11:10 EDT 2019. Contains 321329 sequences. (Running on oeis4.)