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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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified March 29 08:13 EDT 2024. Contains 371265 sequences. (Running on oeis4.)