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A044043 Number of tilings of 2 X n rectangle with polyominoes, each of which has area = # of adjacent polyominoes. 0
0, 0, 2, 5, 3, 9, 23, 25, 44, 113, 161, 244, 561, 930, 1405, 2865, 5137, 8062, 15082, 27806, 45582, 81210, 149637, 254034, 442904, 806389, 1400830, 2428499, 4362924, 7674434, 13329558, 23699803, 41904969, 73097351, 129121535, 228531847 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..36.

FORMULA

Complicated linear recurrence in terms of 4 variables known.

Empirical G.f.: -x^3*(2*x^8+4*x^5+4*x^4+3*x^3+3*x^2+5*x+2) / (2*x^10+4*x^7+3*x^6+x^5+2*x^4+3*x^3-1). [Colin Barker, Nov 29 2012]

EXAMPLE

a(5)=3 because of the tilings

aaabb aabbb abbbc

ccddd cccdd adddc

CROSSREFS

Sequence in context: A193972 A332357 A305126 * A133128 A057337 A163233

Adjacent sequences:  A044040 A044041 A044042 * A044044 A044045 A044046

KEYWORD

nonn

AUTHOR

I seem to have no record of the source for this sequence - N. J. A. Sloane.

STATUS

approved

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Last modified October 15 21:38 EDT 2021. Contains 348034 sequences. (Running on oeis4.)