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%I #10 Jan 03 2017 02:40:03
%S 1,1,3,2,3,18,1382,12,32553,87734,1047666,2796588,1418184546,23685516,
%T 366420255876,13785346041608,23127963123651,2729316555918,
%U 52630543106106954746,1850522471899932,4699488932936084196918,18241171727016849632292,91090700441348806587348
%N Numerators of coefficients of asymptotic expansion related to iterated sine function.
%D N. G. de Bruijn, Asymptotic Methods in Analysis, North-Holland, 3rd. ed., 1970; see p. 158, (8.6.4).
%H G. C. Greubel, <a href="/A059239/b059239.txt">Table of n, a(n) for n = 0..314</a>
%F a(n) = numerator ( (1-2*n)*(-12)^n*Bernoulli(2*n)/(2*n)! ).
%e 1, 1, 3/5, 2/7, 3/25, 18/385, 1382/79625, 12/1925, 32553/14889875, 87734/116491375, 1047666/4094715625, 2796588/32534376875 = A059239/A059240.
%p a:= n-> numer((1-2*n)*(-12)^n*bernoulli(2*n)/(2*n)!): seq (a(n), n=0..30);
%t Numerator[Table[(1 - 2*n)*(-12)^n*BernoulliB[2*n]/(2*n)!, {n,0,25}]] (* _G. C. Greubel_, Jan 02 2017 *)
%Y Cf. A059240.
%K nonn,easy,frac
%O 0,3
%A _N. J. A. Sloane_, Jan 21 2001