%I #12 Mar 24 2023 02:49:54

%S 1,2,4,48,384,1920,46080,645120,5160960,185794560,530841600,

%T 40874803200,280284364800,51011754393600,714164561510400,

%U 42849873690624000,1371195958099968000,302731575164928000,1678343852714360832000,100120983364435968000,1275541328062914232320000

%N Denominators of numbers with g.f. exp(1-(1-x)^(1/2)).

%H Robert Israel, <a href="/A143968/b143968.txt">Table of n, a(n) for n = 0..406</a>

%e 1, 1/2, 1/4, 7/48, 37/384, 133/1920, 2431/46080, 27007/645120, 176761/5160960, ...

%p S:= series(exp(1-(1-x)^(1/2)),x,21):

%p seq(denom(coeff(S,x,i)),i=0..20); # _Robert Israel_, Mar 23 2023

%t CoefficientList[Series[Exp[1-Sqrt[1-x]],{x,0,20}],x]//Denominator (* _Harvey P. Dale_, Sep 13 2019 *)

%Y Cf. A143991 (numerators), A001515.

%K nonn,frac

%O 0,2

%A _N. J. A. Sloane_, Dec 02 2008