Number of tilings of a 5 X n rectangle using n pentominoes of shapes F, L, Y.

Terms

a(0) =1a(1) =0a(2) =2a(3) =0a(4) =6a(5) =16a(6) =32a(7) =104a(8) =186a(9) =800a(10) =1700a(11) =4836a(12) =11186a(13) =29940a(14) =84388a(15) =208808a(16) =563364a(17) =1391664a(18) =3787510a(19) =9824684a(20) =25712276a(21) =66815444a(22) =173151378a(23) =457266220a(24) =1188536784a(25) =3113743272a(26) =8087358736a(27) =21152284376a(28) =55283003950a(29) =144314582896