(color online) Phase diagrams of the Kitaev tubes composed of even and odd number of chains, which belongs to class BDI. The tube is composed of 6 Kitaev chains for the upper panel, while 5 chains for the lower panel. t_x is chosen as energy unit. Δ x = 0.8 and t y = 0.6 . The integer numbers in the figure represent the Z index. In the regions where μ < 2 ( t x − t y ) = 0.8 , the topological indices are 2,4,6 for M = 6 (upper panel) and 1,3,5 for M = 5 (lower panel).