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A129153 Rencontres numbers: permutations with exactly 8 fixed points. 9
1, 0, 45, 330, 4455, 56628, 795795, 11930490, 190900710, 3245287760, 58415223438, 1109889169740, 22197783520770, 466153453732680, 10255375982438730, 235873647595600476, 5660967542295146895, 141524188557377590800 (list; graph; refs; listen; history; text; internal format)
OFFSET

8,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 8..200

FORMULA

E.g.f.: exp(-x)/(1-x)*(x^8/8!). [Joerg Arndt, Feb 19 2014]

O.g.f.: (1/8!)*Sum_{k>=8} k!*x^k/(1 + x)^(k+1). - Ilya Gutkovskiy, Apr 15 2017

MAPLE

a:= n-> -sum((n-1)!*sum((-1)^k/(k-7)!, j=0..n-1), k=7..n-1)/8!: seq(a(n), n=8..30);

MATHEMATICA

With[{nn=40}, Drop[CoefficientList[Series[Exp[-x]/(1 - x) x^8/8!, {x, 0, nn}], x]Range[0, nn]!, 8]] (* Vincenzo Librandi, Feb 19 2014 *)

PROG

(PARI) x='x+O('x^66); Vec( serlaplace(exp(-x)/(1-x)*(x^8/8!)) ) \\ Joerg Arndt, Feb 19 2014

CROSSREFS

Column k=8 of A008290.

Cf. A000166, A000240, A000387, A000449, A000475, A129135, A129136, A129149, A129217, A129218, A129238, A129255, A008291, A170942.

Sequence in context: A324458 A073873 A272850 * A156719 A228059 A155015

Adjacent sequences:  A129150 A129151 A129152 * A129154 A129155 A129156

KEYWORD

nonn

AUTHOR

Zerinvary Lajos, May 25 2007

EXTENSIONS

Changed offset from 0 to 8 by Vincenzo Librandi, Feb 19 2014

STATUS

approved

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Last modified May 30 08:43 EDT 2020. Contains 334712 sequences. (Running on oeis4.)