Number of ways to tile a 3 X n strip with dominoes and L-shaped 5-minoes.

Terms

a(0) =1a(1) =0a(2) =3a(3) =8a(4) =13a(5) =52a(6) =119a(7) =308a(8) =873a(9) =2184a(10) =5867a(11) =15552a(12) =40581a(13) =107836a(14) =283871a(15) =748076a(16) =1976545a(17) =5208784a(18) =13743315a(19) =36260088a(20) =95627773a(21) =252289476a(22) =665499975a(23) =1755466916a(24) =4630903129a(25) =12215645848a(26) =32223689915a(27) =85003275440a(28) =224228961909a(29) =591494654412