This site is supported by donations to The OEIS Foundation.

"Email this user" was broken Aug 14 to 9am Aug 16. If you sent someone a message in this period, please send it again.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A114244 a(n) = (n+1)(n+2)^2*(n+3)(7n^2 + 28n + 30)/360. 2
 1, 13, 76, 295, 889, 2254, 5040, 10242, 19305, 34243, 57772, 93457, 145873, 220780, 325312, 468180, 659889, 912969, 1242220, 1664971, 2201353, 2874586, 3711280, 4741750, 6000345, 7525791, 9361548, 11556181, 14163745, 17244184, 20863744 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS KekulĂ© numbers for certain benzenoids. First differences of A114242. - Peter Bala, Sep 21 2007 REFERENCES S. J. Cyvin and I. Gutman, KekulĂ© structures in benzenoid hydrocarbons, Lecture Notes in Chemistry, No. 46, Springer, New York, 1988 (pp. 167-169, Table 10.5/II/5). LINKS FORMULA G.f.: (1+x)(1 + 5x + x^2)/(1-x)^7. MAPLE a:=n->(n+1)*(n+2)^2*(n+3)*(7*n^2+28*n+30)/360: seq(a(n), n=0..35); CROSSREFS Cf. A114242. Sequence in context: A051361 A114070 A005340 * A050485 A034265 A282643 Adjacent sequences:  A114241 A114242 A114243 * A114245 A114246 A114247 KEYWORD nonn,easy AUTHOR Emeric Deutsch, Nov 18 2005 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.