|
| |
|
|
A036760
|
|
Number of tree-like octagonal systems.
|
|
0
| |
|
|
1, 1, 3, 11, 56, 341, 2351, 17329, 133126, 1052813, 8511339, 70050568, 585226579, 4952310082, 42376979857, 366185395267, 3191787761573, 28036397185485, 247982793594183, 2207183342498485, 19756959439608022, 177765564883970415
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,3
|
|
|
REFERENCES
| J. Brunvoll et al., Enumeration of tree-like octagonal systems, J. Math. Chem., 21 (1997), 193-196.
S. J. Cyvin et al., Enumeration of tree-like octagonal systems: catapolyoctagons, ACH Models in Chem. 134 (1997), 55-70.
|
|
|
FORMULA
| G.f.=[2x + (2-7x)U(x) - (1+7x)U^2(x) + 2(2-x)V(x) + 4(1+x)U(x^2) + 3xU^2(x^2) + 2xU(x^4)]/8, where U(x) is the g.f. of A036758 and V(x) is the g.f. of A036759. - Emeric Deutsch (deutsch(AT)duke.poly.edu), May 04 2004
|
|
|
CROSSREFS
| Cf. A036758, A036759.
Sequence in context: A136104 A174627 A007841 * A000985 A094611 A052442
Adjacent sequences: A036757 A036758 A036759 * A036761 A036762 A036763
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
EXTENSIONS
| More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), May 04 2004
|
| |
|
|
