Number of (undirected) Hamiltonian paths in n-Moebius ladder.

Terms

a(0) =0a(1) =4a(2) =12a(3) =36a(4) =72a(5) =140a(6) =228a(7) =364a(8) =528a(9) =756a(10) =1020a(11) =1364a(12) =1752a(13) =2236a(14) =2772a(15) =3420a(16) =4128a(17) =4964a(18) =5868a(19) =6916a(20) =8040a(21) =9324a(22) =10692a(23) =12236a(24) =13872a(25) =15700a(26) =17628a(27) =19764a(28) =22008a(29) =24476