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

A219867

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

Terms

    a(0) =1a(1) =1a(2) =4a(3) =14a(4) =41a(5) =143a(6) =472a(7) =1562a(8) =5233a(9) =17395a(10) =58002a(11) =193346a(12) =644219a(13) =2147421a(14) =7156704a(15) =23852324a(16) =79497767a(17) =264952955a(18) =883057354a(19) =2943113598a(20) =9809007073a(21) =32692164351a(22) =108958689984a(23) =363145140266

External references