Number of tilings of a 7 X n rectangle using straight (3 X 1) trominoes and 2 X 2 tiles.

A219971

Number of tilings of a 7 X n rectangle using straight (3 X 1) trominoes and 2 X 2 tiles.

Terms

    a(0) =1a(1) =0a(2) =3a(3) =13a(4) =31a(5) =170a(6) =804a(7) =2744a(8) =12343a(9) =55657a(10) =214485a(11) =923990a(12) =4008013a(13) =16241904a(14) =68963484a(15) =293830787a(16) =1216393406a(17) =5135225641a(18) =21711233759a(19) =90692128053a(20) =381960417890

External references