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A272108 Numerators of coefficients of the series of sqrt(-log(1-q)/q). 2

%I #23 Mar 16 2018 10:14:22

%S 1,1,13,35,6271,2211,2760011,1875133,557576779,13761972821,

%T 3244313727791,185892006151,77616670784995799,3796517116479937,

%U 1261429981603803133,4682424392750614127,71254131149637283370867,385105979676360971447,2401927688678818378270288001

%N Numerators of coefficients of the series of sqrt(-log(1-q)/q).

%C The function sqrt(-log(1-q)/q) is associated with the generating function of connected graphs enumeration

%H Vincenzo Librandi, <a href="/A272108/b272108.txt">Table of n, a(n) for n = 0..200</a>

%H P. Flajolet, B. Salvy, and G. Schaeffer, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v11i1r34 ">Airy Phenomena and Analytic Combinatorics of Connected Graphs</a>, Electronic Journal of Combinatorics, Volume 11(1), 2004, Research Paper #R34 page 8.

%e Coefficients begin: 1, 1/4, 13/96, 35/384, 6271/92160, ...

%p gf := sqrt(-log(1-q)/q) ;

%p taylor(%,q=0,18) ;

%p gfun[seriestolist](%) ;

%p map(numer,%) ; # _R. J. Mathar_, Mar 15 2018

%t s = Sqrt[Log[1/(1 - q)]/q] + O[q]^20; CoefficientList[s, q] // Numerator

%o (PARI) Vec(apply(numerator, sqrt(-log(1-'q)/'q))) \\ _M. F. Hasler_, Mar 16 2018

%Y Cf. A272109 (denominators).

%K nonn,frac

%O 0,3

%A _Jean-François Alcover_, Apr 20 2016

%E Definition corrected by _Juan Arias-de-Reyna_, Mar 15 2018

%E Edited by _M. F. Hasler_, Mar 16 2018

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Last modified May 18 06:11 EDT 2024. Contains 372618 sequences. (Running on oeis4.)