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A032037 Doubles (index 2+) under "AIJ" (ordered, indistinct, labeled) transform. 3
1, 2, 18, 264, 5400, 141840, 4551120, 172529280, 7545363840, 373944211200, 20711190931200, 1267784551756800, 84991791159475200, 6193091146059417600, 487361761916020992000, 41192820513212239872000, 3721763273059549605888000, 357950394802026289815552000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..200

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 92

FORMULA

a(n) = n!*A001003(n-1). - Vladeta Jovovic, Dec 06 2002

E.g.f.: series reversion of x*(1-2*x)/(1-x). - Andrew Howroyd, Sep 19 2018

MATHEMATICA

a[1]=1; a[2]=2; a[n_] := a[n]=3(2n-3)a[n-1]-(n-1)(n-3)a[n-2]

PROG

(PARI) Vec(serlaplace(serreverse(x*(1-2*x)/(1-x) + O(x^20)))) \\ Andrew Howroyd, Sep 19 2018

CROSSREFS

Sequence in context: A099880 A141009 A143154 * A138275 A292693 A295183

Adjacent sequences:  A032034 A032035 A032036 * A032038 A032039 A032040

KEYWORD

nonn

AUTHOR

Christian G. Bower

EXTENSIONS

Terms a(17) and beyond from Andrew Howroyd, Sep 19 2018

STATUS

approved

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Last modified October 19 19:55 EDT 2018. Contains 316378 sequences. (Running on oeis4.)