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A009725 Expansion of tan(x)*(1+x). 2

%I

%S 0,1,2,2,8,16,96,272,2176,7936,79360,353792,4245504,22368256,

%T 313155584,1903757312,30460116992,209865342976,3777576173568,

%U 29088885112832,581777702256640,4951498053124096,108932957168730112,1015423886506852352,24370173276164456448

%N Expansion of tan(x)*(1+x).

%F E.g.f.: x*(1+x)*Q(0), where Q(k) = 1 - x^2/(x^2 - (2*k+1)*(2*k+3)/Q(k+1) ); (continued fraction). - _Sergei N. Gladkovskii_, Dec 16 2013

%t Tan[ x ]*(1+x)

%Y a(2n) = A009752(n), a(2n+1) = A000182(n+1).

%K nonn,easy

%O 0,3

%A _R. H. Hardin_

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Last modified February 25 22:27 EST 2018. Contains 299662 sequences. (Running on oeis4.)