A236583 - OEIS

%I #10 Nov 28 2016 01:48:07

%S 1,1,4,11,33,96,281,821,2400,7015,20505,59936,175193,512089,1496836,

%T 4375251,12788857,37381824,109267057,319387565,933569728,2728823951,

%U 7976351345,23314871872,68149361393

%N The number of tilings of an 8 X (3n) floor with 2 X 3 hexominoes.

%C Tilings are counted irrespective of internal symmetry: Tilings that match each other after rotations and/or reflections are counted with their multiplicity.

%H R. J. Mathar, <a href="http://arxiv.org/abs/1311.6135">Paving rectangular regions...</a>, arXiv:1311.6135, Table 51.

%H R. J. Mathar, <a href="http://arxiv.org/abs/1406.7788">Tilings of Rectangular Regions by Rectangular Tiles: Counts Derived from Transfer Matrices</a>, arXiv:1406.7788 [math.CO], eq. (34).

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (3,0,-1,1).

%F G.f.: (-1+x)^2/(x^3-x^4+1-3*x).

%p g := (-1+x)^2/(x^3-x^4+1-3*x) ;

%p taylor(%,x=0,30) ;

%p gfun[seriestolist](%) ;

%Y Cf. A000079 (5 X n floor), A182097 (6 X n floor), A000244 (7 X n floor), A236584 (9 x 2n floor)

%K easy,nonn

%O 0,3

%A _R. J. Mathar_, Jan 29 2014