A270063 Number of tilings of a 3 X n rectangle using monominoes and trominoes of any shape.

1, 2, 14, 93, 590, 3710, 23509, 148796, 940916, 5952243, 37655502, 238204978, 1506870209, 9532433288, 60301864000, 381467462217, 2413150656124, 15265511608858, 96569119066667, 610893045560410, 3864489168524208, 24446630393071735, 154648573589573678

Offset: 0

Author

Alois P. Heinz, Mar 09 2016

Keywords

• nonn
• easy

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..1000

Crossrefs

Column k=3 of A270061.

Cf. A134438.

Formula

G.f.: -(x^15 +2*x^14 +5*x^13 -4*x^12 -7*x^11 -21*x^10 +12*x^9 +11*x^8 +24*x^7 -21*x^6 -13*x^5 +16*x^3 +2*x^2 +2*x -1) / (x^18 +2*x^17 +5*x^16 -9*x^15 -21*x^14 -54*x^13 +32*x^12 +46*x^11 +147*x^10 +21*x^9 -40*x^8 -110*x^7 -17*x^6 -11*x^5 -32*x^4 -37*x^3 -8*x^2 -4*x +1).