Number of tilings of a 20 X n rectangle using 2n decominoes of shape I.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =1a(9) =1a(10) =13a(11) =27a(12) =43a(13) =61a(14) =81a(15) =103a(16) =127a(17) =153a(18) =181a(19) =211a(20) =484a(21) =967a(22) =1714a(23) =2785a(24) =4246a(25) =6169a(26) =8632a(27) =11719a(28) =15520a(29) =20131