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 A117643 a(n) = n*(a(n-1)-1) starting with a(0)=3. 0
 3, 2, 2, 3, 8, 35, 204, 1421, 11360, 102231, 1022300, 11245289, 134943456, 1754264915, 24559708796, 368395631925, 5894330110784, 100203611883311, 1803665013899580, 34269635264092001, 685392705281840000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Starting with a(0)=0 would give -A007526(n); starting with a(0)=1 would give -A038156(n). In general, for this recurrence, a(n) = ceiling(1 + n!*(a(0)-e)) for n>0; this is the first case with positive terms. LINKS FORMULA a(n) = ceiling(1 + n!*(3-e)) for n>0. a(n) = 3*n! - n! * sum_{k=0..n} 1/(k-1)!, with n>=0. - Paolo P. Lava, Oct 07 2008 a(n) = n! - floor(e*n!) + 1, n>0. - Gary Detlefs, Jun 06 2010 EXAMPLE a(5) = 5*(a(4)-1) = 5*(8-1) = 35. MATHEMATICA a=3; Table[a=a*n-n, {n, 1, 2*4!}] (* Vladimir Joseph Stephan Orlovsky, Apr 22 2010 *) RecurrenceTable[{a[0]==3, a[n]==n(a[n-1]-1)}, a, {n, 20}] (* Harvey P. Dale, Jul 17 2018 *) CROSSREFS Sequence in context: A032450 A046460 A327661 * A141862 A237612 A111739 Adjacent sequences:  A117640 A117641 A117642 * A117644 A117645 A117646 KEYWORD easy,nonn AUTHOR Henry Bottomley, Apr 10 2006 STATUS approved

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Last modified May 15 07:51 EDT 2021. Contains 343909 sequences. (Running on oeis4.)