A045627 Number of 2n-bead black-white reversible strings with n black beads and fundamental period 2n.
1, 1, 3, 9, 34, 125, 459, 1715, 6432, 24300, 92375, 352715, 1352034, 5200299, 20058297, 77558625, 300540160, 1166803109, 4537567188, 17672631899, 68923264250, 269128935495, 1052049481857, 4116715363799, 16123801834656
Offset: 0
Keywords
Formula
Moebius transform of A032123(n+1) (Christian Bower).