%I A003048
%S A003048 1,2,3,10,39,196,1175,8226,65807,592264,5922639,65149030,
%T A003048 781788359,10163248668,142285481351,2134282220266,34148515524255,
%U A003048 580524763912336,10449445750422047,198539469258018894
%N A003048 a(n+1)=n*a(n)-(-1)^n.
%F A003048 E.g.f.: (2-exp(-x))/(1-x) (if offset 0).
%F A003048 a(n+2)=n(a(n)+a(n+1)) for n>0. - Amarnath Murthy (amarnath_murthy(AT)yahoo.com),
Oct 05 2002
%p A003048 a:= proc(p) option remember; p*a(p-1)-(-1)^p end proc: a(0):= 1: seq(a(p),
p=0..19); - Robert Israel, Jan 05 2008
%t A003048 a[0] = 1; a[p_] := p*a[p - 1] -(-1)^p; a /@ Range[0, 19] - Zerinvary
Lajos (zerinvarylajos(AT)yahoo.com), Mar 29 2007
%o A003048 (PARI) a(n)=if(n<2,n>0,(n-1)*a(n-1)+(-1)^n)
%o A003048 (PARI) a(n)=if(n<1,0,(n-1)!*polcoeff((2-exp(-x+O(x^n)))/(1-x),n-1))
%Y A003048 a(n)=(n-1)!+A002467(n), n>0.
%Y A003048 Sequence in context: A141102 A144720 A164933 this_sequence A008980 A064183
A050381
%Y A003048 Adjacent sequences: A003045 A003046 A003047 this_sequence A003049 A003050
A003051
%K A003048 nonn
%O A003048 1,2
%A A003048 N. J. A. Sloane (njas(AT)research.att.com).
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