%I #11 Oct 30 2013 10:39:12
%S 1,1,1,2,11,16,301,272,16631,7936,1620601,353792,250557251,
%T 22368256,56629836901,1903757312,17602836565871,209865342976,
%U 7193368568377201,29088885112832,3735581618747946491
%N exp(arcsinh(tanh(x))) = 1+x+1/2!*x^22/3!*x^311/4!*x^4+16/5!*x^5...
%H Alois P. Heinz, <a href="/A012253/b012253.txt">Table of n, a(n) for n = 0..200</a>
%F a(n) ~ n! * (cos(n*Pi/2)) * (4/Pi)^n / n^(3/2), if n is even and a(n) ~ n! * 2 * sin(n*Pi/2) * (2/Pi)^(n+1), if n is odd.  _Vaclav Kotesovec_, Oct 30 2013
%t CoefficientList[Series[Exp[ArcSinh[Tanh[x]]], {x, 0, 20}], x]* Range[0, 20]! (* _Vaclav Kotesovec_, Oct 30 2013 *)
%Y Bisections are (1)^n*A000182 and (1)^n*A012079.
%K sign
%O 0,4
%A Patrick Demichel (patrick.demichel(AT)hp.com)
