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 A108650 a(n) = (n+1)^2*(n+2)*(n+3)*(3*n+4)/24. 2
 1, 14, 75, 260, 700, 1596, 3234, 6000, 10395, 17050, 26741, 40404, 59150, 84280, 117300, 159936, 214149, 282150, 366415, 469700, 595056, 745844, 925750, 1138800, 1389375, 1682226, 2022489, 2415700, 2867810, 3385200, 3974696, 4643584 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS KekulĂ© numbers for certain benzenoids. a(n) = A001477*A001296 or n*A001296. - Zerinvary Lajos, Jan 20 2007 REFERENCES S. J. Cyvin and I. Gutman, KekulĂ© structures in benzenoid hydrocarbons, Lecture Notes in Chemistry, No. 46, Springer, New York, 1988 (p. 230, no. 26). LINKS Bo Gyu Jeong, Table of n, a(n) for n = 0..5000 C. Krishnamachari, The operator (xD)^n, J. Indian Math. Soc., 15 (1923),3-4. [Annotated scanned copy] FORMULA a(n) = (n+1)*stirling2(n+3,n+1). - Zerinvary Lajos, Jan 20 2007 MAPLE a:= n-> (n+1)^2*(n+2)*(n+3)*(3*n+4)/24: seq(a(n), n=0..36); seq((n+1)*stirling2(n+3, n+1), n=0..32); # Zerinvary Lajos, Jan 20 2007 MATHEMATICA Table[((n+1)^2 (n+2)(n+3)(3n+4))/24, {n, 0, 40}] (* or *) Table[n StirlingS2[n+2, n], {n, 40}] (* Harvey P. Dale, Dec 01 2013 *) CROSSREFS Sequence in context: A205583 A167633 A196411 * A093567 A296996 A270704 Adjacent sequences:  A108647 A108648 A108649 * A108651 A108652 A108653 KEYWORD nonn AUTHOR Emeric Deutsch, Jun 13 2005 STATUS approved

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Last modified January 18 20:57 EST 2019. Contains 319282 sequences. (Running on oeis4.)