|
Search: id:A110159
|
|
|
| A110159 |
|
a(n)=(n+1)(n+2)(n+3)(9n^2+26n+20)/120. |
|
+0 1
|
|
| 1, 11, 54, 179, 469, 1050, 2100, 3858, 6633, 10813, 16874, 25389, 37037, 52612, 73032, 99348, 132753, 174591, 226366, 289751, 366597, 458942, 569020, 699270, 852345, 1031121, 1238706, 1478449, 1753949, 2069064, 2427920, 2834920, 3294753
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
COMMENT
|
Kekule numbers for certain benzenoids.
|
|
REFERENCES
|
S. J. Cyvin and I. Gutman, Kekule structures in benzenoid hydrocarbons, Lecture Notes in Chemistry, No. 46, Springer, New York, 1988 (pp. 167-170, Table 10.5/II/6).
|
|
FORMULA
|
G.f.=(1+5x+3x^2)/(1-x)^6.
|
|
MAPLE
|
a:=n->(n+1)*(n+2)*(n+3)*(9*n^2+26*n+20)/120: seq(a(n), n=0..35);
|
|
CROSSREFS
|
Sequence in context: A104291 A003867 A059135 this_sequence A061983 A079884 A050900
Adjacent sequences: A110156 A110157 A110158 this_sequence A110160 A110161 A110162
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Emeric Deutsch (deutsch(AT)duke.poly.edu), Nov 18 2005
|
|
|
Search completed in 0.002 seconds
|