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A165793 a(0)=1, a(n)=n*(a(n-1)-2). 3
1, -1, -6, -24, -104, -530, -3192, -22358, -178880, -1609938, -16099400, -177093422, -2125121088, -27626574170, -386772038408, -5801580576150, -92825289218432, -1578029916713378, -28404538500840840 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..250

FORMULA

a(n) = n! - 2*floor(e*n!)+2 , n>0. - Gary Detlefs, Jun 19 2010

MATHEMATICA

RecurrenceTable[{a[0]==1, a[n]==n*(a[n-1]-2)}, a[n], {n, 30}] (* Harvey P. Dale, Jul 19 2011 *)

FoldList[#1*#2 - 2 #2 &, 1, Range[25]] (* G. C. Greubel, Apr 08 2016 *)

CROSSREFS

Sequence in context: A120583 A089378 A074414 * A122740 A034432 A026962

Adjacent sequences:  A165790 A165791 A165792 * A165794 A165795 A165796

KEYWORD

sign

AUTHOR

Philippe Deléham, Sep 26 2009

EXTENSIONS

Corrected by Harvey P. Dale, Jul 19 2011

STATUS

approved

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Last modified December 6 07:11 EST 2019. Contains 329785 sequences. (Running on oeis4.)