A000947 Number of free nonplanar polyenoids with n nodes and symmetry point group C_{2v}.

1, 2, 4, 10, 15, 44, 56, 177, 212, 706, 792, 2714, 2961

Offset

7,2

Links

Table of n, a(n) for n=7..19.

S. J. Cyvin, J. Brunvoll, E. Brendsdal, B. N. Cyvin and E. K. Lloyd, Enumeration of polyene hydrocarbons: a complete mathematical solution, J. Chem. Inf. Comput. Sci., 35 (1995) 743-751.

S. J. Cyvin, J. Brunvoll, E. Brendsdal, B. N. Cyvin and E. K. Lloyd, Enumeration of polyene hydrocarbons: a complete mathematical solution, J. Chem. Inf. Comput. Sci., 35 (1995) 743-751. [Annotated scanned copy]

Formula

a(n) = A000063(n + 2) - A000936(n). - Sean A. Irvine, Oct 15 2015

Crossrefs

Sequence in context: A128513 A048200 A058201 * A125245 A371896 A358317

Adjacent sequences: A000944 A000945 A000946 * A000948 A000949 A000950

Keyword

nonn,more

Author

E. K. Lloyd (E.K.Lloyd(AT)soton.ac.uk)

Extensions

a(16)-a(19) and title improved by Sean A. Irvine, Oct 16 2015

Status

approved