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A224098
Denominators of poly-Cauchy numbers c_n^(4).
3
1, 16, 1296, 6912, 6480000, 2592000, 6223392000, 14224896000, 1440270720000, 320060160000, 2811600481536000, 511200087552000, 255506749760021760000, 291175783202304000, 16846598885276160000
OFFSET
0,2
COMMENTS
The poly-Cauchy numbers c_n^(k) can be expressed in terms of the (unsigned) Stirling numbers of the first kind: c_n^(k) = (-1)^n*sum(abs(stirling1(n,m))*(-1)^m/(m+1)^k, m=0..n).
LINKS
Takao Komatsu, Poly-Cauchy numbers, RIMS Kokyuroku 1806 (2012)
Takao Komatsu, Poly-Cauchy numbers with a q parameter, Ramanujan J. 31 (2013), 353-371.
Takao Komatsu, Poly-Cauchy numbers, Kyushu J. Math. 67 (2013), 143-153.
T. Komatsu, V. Laohakosol, K. Liptai, A generalization of poly-Cauchy numbers and its properties, Abstract and Applied Analysis, Volume 2013, Article ID 179841, 8 pages.
Takao Komatsu, FZ Zhao, The log-convexity of the poly-Cauchy numbers, arXiv preprint arXiv:1603.06725, 2016
MATHEMATICA
Table[Denominator[Sum[StirlingS1[n, k]/ (k + 1)^4, {k, 0, n}]], {n, 0, 25}]
PROG
(PARI) a(n) = denominator(sum(k=0, n, stirling(n, k, 1)/(k+1)^4)); \\ Michel Marcus, Nov 15 2015
CROSSREFS
Cf. A006233, A222748, A224094, A224096, A224099 (numerators).
Sequence in context: A363921 A027648 A224105 * A016828 A072161 A173544
KEYWORD
nonn,frac
AUTHOR
Takao Komatsu, Mar 31 2013
STATUS
approved