|
Search: id:A107278
|
|
|
| A107278 |
|
Number of spiro bicyclic skeletons with n carbon atoms (see Parks et al. for precise definition). |
|
+0
1
|
|
| 1, 4, 17, 60, 209, 685, 2204, 6913, 21387, 65241, 197104, 590284, 1755804, 5191723, 15276610, 44761350, 130682371, 380337474, 1103927291, 3196494453
(list; graph; listen)
|
|
|
OFFSET
|
6,2
|
|
|
REFERENCES
|
Camden A. Parks and James B. Hendrickson, Enumeration of monocyclic and bicyclic carbon skeletons, J. Chem. Inf. Comput. Sci., vol. 31, 334-339 (1991).
|
|
FORMULA
|
G.f.:(1+2*x)/(1-2*x-3*x^2) . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 09 2006
|
|
CROSSREFS
|
Table III of the Parks et al. reference has 4 sequences: A121158, A121159, A121160 and this sequence.
Sequence in context: A121327 A027075 A034331 this_sequence A006762 A122231 A119916
Adjacent sequences: A107275 A107276 A107277 this_sequence A107279 A107280 A107281
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com), Sep 10 2006
|
|
|
Search completed in 0.002 seconds
|
