Number of base 8 n-digit numbers with adjacent digits differing by one or less.

Terms

a(0) =1a(1) =8a(2) =22a(3) =62a(4) =176a(5) =502a(6) =1436a(7) =4116a(8) =11814a(9) =33942a(10) =97582a(11) =280676a(12) =807574a(13) =2324116a(14) =6689624a(15) =19257202a(16) =55439298a(17) =159611886a(18) =459545688a(19) =1323132230a(20) =3809653732a(21) =10969153364a(22) =31583803574a(23) =90940708414a(24) =261850874726a(25) =753964626300