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A272109
Denominators of coefficients of the series of sqrt(-log(1-q)/q).
2
1, 4, 96, 384, 92160, 40960, 61931520, 49545216, 16986931200, 475634073600, 125567395430400, 7972533043200, 3656522554933248000, 195014536263106560, 70205233054718361600, 280820932218873446400, 4582997613812014645248000, 26453088680011628544000
OFFSET
0,2
COMMENTS
The function sqrt(-log(1-q)/q) is associated with the generating function of connected graphs enumeration
LINKS
P. Flajolet, B. Salvy, and G. Schaeffer, Airy Phenomena and Analytic Combinatorics of Connected Graphs, Electronic Journal of Combinatorics, Volume 11(1), 2004, Research Paper #R34 page 8.
MAPLE
gf := sqrt(-log(1-q)/q) ;
taylor(%, q=0, 18) ;
gfun[seriestolist](%) ;
map(denom, %) ; # R. J. Mathar, Mar 15 2018
MATHEMATICA
s = Sqrt[Log[1/(1 - q)]/q] + O[q]^20; CoefficientList[s, q] // Denominator
PROG
(PARI) Vec(apply(denominator, sqrt(-log(1-'q)/'q))) \\ M. F. Hasler, Mar 16 2018
CROSSREFS
Cf. A272108 (numerators).
Sequence in context: A302121 A188895 A068114 * A203316 A359653 A202682
KEYWORD
nonn,frac
AUTHOR
EXTENSIONS
Definition corrected by Juan Arias-de-Reyna, Mar 15 2018
STATUS
approved