|
Search: id:A110695
|
|
|
| A110695 |
|
Kekule numbers for certain benzenoids of trigonal symmetry. |
|
+0 1
|
|
| 1, 9, 341, 14859, 671509, 31816259, 1575219491, 80813149559, 4262996933909, 229858972288659, 12613108252122091, 702092835479959559, 39548041458039952291, 2250117073947022121799, 129122621276859925669799
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
REFERENCES
|
S. J. Cyvin and I. Gutman, Kekule structures in benzenoid hydrocarbons, Lecture Notes in Chemistry, No. 46, Springer, New York, 1988 (see p 313).
|
|
FORMULA
|
a(n)=[2binomial(2n, n)-1][binomial(2n, n)^2-binomial(2n, n)+1].
|
|
MAPLE
|
a:=n->(2*binomial(2*n, n)-1)*(binomial(2*n, n)^2-binomial(2*n, n)+1); seq(a(n), n=0..16);
|
|
CROSSREFS
|
Sequence in context: A090085 A098650 A098652 this_sequence A157589 A055601 A012812
Adjacent sequences: A110692 A110693 A110694 this_sequence A110696 A110697 A110698
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Emeric Deutsch (deutsch(AT)duke.poly.edu), Aug 03 2005
|
|
|
Search completed in 0.002 seconds
|