A045905 Catafusenes (see reference for precise definition).

0, 0, 0, 0, 1, 2, 16, 80, 473, 2517, 13431, 69357, 353943, 1780894, 8886254, 44024308, 217021967, 1065653519, 5217704239, 25491204743, 124335254416, 605720277647, 2948274685881, 14341442951945, 69732440151924

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn

References

• S. J. Cyvin et al., Enumeration and classification of certain polygonal systems... : annelated catafusenes, J. Chem. Inform. Comput. Sci., 34 (1994), 1174-1180, ^4O = ^4F_7 page 1178.

Crossrefs

Last column of A121178.

Formula

8*a(n) = A045829(n) + 3*A045445(n/2) + 2*A002212(n/4) + 2*A039660(n) for n > 0, where sequence values with non-integer index are implicitly defined as 0. - R. J. Mathar, Jul 30 2019