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A280781 Denominators of coefficients in asymptotic expansion of S_n (number of simple permutations, A111111).

%I A280781 #20 Jan 22 2017 21:28:15
%S A280781 1,1,1,3,3,15,45,315,63,2835,14175,22275,467775,1216215,42567525,
%T A280781 638512875,638512875,834978375,558242685,1856156927625,713906510625,
%U A280781 17717861581875,2143861251406875,9861761756471625,147926426347074375,75472666503609375,48076088562799171875
%N A280781 Denominators of coefficients in asymptotic expansion of S_n (number of simple permutations, A111111).
%C A280781 Has the same start as A046983 but is a different sequence.
%H A280781 Gheorghe Coserea, <a href="/A280781/b280781.txt">Table of n, a(n) for n = 0..100</a>
%H A280781 Michael Borinsky, <a href="https://arxiv.org/abs/1603.01236">Generating asymptotics for factorially divergent sequences</a>, arXiv preprint arXiv:1603.01236 [math.CO], 2016.
%e A280781 Coefficients are 1, -4, 2, -40/3, -182/3, -7624/15, -202652/45, -14115088/315, -30800534/63, -16435427656/2835, ...
%o A280781 (PARI)
%o A280781 seq(N) = {
%o A280781   my(f = serreverse(x*Ser(vector(N, n, n!))));
%o A280781   Vec(x* f'/f * exp(2 + (f-x)/(x*f)));
%o A280781 };
%o A280781 apply(denominator, seq(28))  \\ _Gheorghe Coserea_, Jan 22 2017
%Y A280781 Cf. A000699, A280775, A111111, A280777, A280778, A280779, A280780.
%Y A280781 Cf. also A046983.
%K A280781 nonn,frac
%O A280781 0,4
%A A280781 _N. J. A. Sloane_, Jan 19 2017
%E A280781 More terms from _Gheorghe Coserea_, Jan 22 2017