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A109123 4(n+1)^2*(n+3)^2*(5n^2+20n+12). 0
432, 9472, 64800, 269568, 842800, 2184192, 4953312, 10163200, 19288368, 34387200, 58238752, 94493952, 147841200, 224186368, 330847200, 476762112, 672713392, 931564800, 1268513568, 1701356800, 2250772272, 2940613632 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

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. 311).

FORMULA

G.f.=16(27+403z+473z^2-15z^3+14z^4-2z^5)/(1-z)^7.

MAPLE

a:=n->4*(n+1)^2*(n+3)^2*(5*n^2+20*n+12): seq(a(n), n=0..28);

CROSSREFS

Sequence in context: A006910 A015229 A174717 * A113921 A047804 A008691

Adjacent sequences:  A109120 A109121 A109122 * A109124 A109125 A109126

KEYWORD

nonn

AUTHOR

Emeric Deutsch (deutsch(AT)duke.poly.edu), Jun 19 2005

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Last modified February 17 18:29 EST 2012. Contains 206068 sequences.