login
A045909
Number of unsymmetrical catafusenes with n hexagons (see reference for precise definition).
2
0, 0, 1, 8, 39, 190, 861, 3943, 17867, 81496, 372378, 1709842, 7879360, 36454004, 169239651, 788311290, 3683018475, 17255646688, 81056033636, 381668479192, 1801188588566, 8517994717214, 40360814900566, 191589547228523, 911009396044132, 4338777661726040
OFFSET
0,4
COMMENTS
Column C_s of Table 6 in Cyvin et al. Computed by subtracting all the other symmetry classes from the total. - Sean A. Irvine, Mar 27 2021
LINKS
S. J. Cyvin, B. N. Cyvin, J. Brunvoll and E. Brendsdal, Enumeration and Classification of Certain Polygonal Systems Representing Polycyclic Conjugated Hydrocarbons: Annelated Catafusenes, Journal of Chemical Information and Modeling [formerly, J. Chem. Inform. Comput. Sci.], 34 (1994), pp. 1174-1180.
FORMULA
a(n) = A045906(n) - A045907(n) - A045908(n/2) - A342554(n/2) - A342570(n/2) - 2*A030529(n/4) - A055879(n/4) - [n=0] with sequences assumed to be 0 for non-integer arguments. - Sean A. Irvine, Mar 27 2021
KEYWORD
nonn
EXTENSIONS
More terms from Sean A. Irvine, Mar 27 2021
STATUS
approved