Number of (directed) Hamiltonian paths in the n-ladder graph.

Terms

a(0) =2a(1) =8a(2) =16a(3) =28a(4) =44a(5) =64a(6) =88a(7) =116a(8) =148a(9) =184a(10) =224a(11) =268a(12) =316a(13) =368a(14) =424a(15) =484a(16) =548a(17) =616a(18) =688a(19) =764a(20) =844a(21) =928a(22) =1016a(23) =1108a(24) =1204a(25) =1304a(26) =1408a(27) =1516a(28) =1628a(29) =1744