Length of longest trail (i.e., path with all distinct edges) on the edges of an n-cube.

Terms

a(0) =0a(1) =1a(2) =4a(3) =9a(4) =32a(5) =65a(6) =192a(7) =385a(8) =1024a(9) =2049a(10) =5120a(11) =10241a(12) =24576a(13) =49153a(14) =114688a(15) =229377a(16) =524288a(17) =1048577a(18) =2359296a(19) =4718593a(20) =10485760a(21) =20971521a(22) =46137344a(23) =92274689a(24) =201326592a(25) =402653185a(26) =872415232a(27) =1744830465a(28) =3758096384a(29) =7516192769