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A317411
Expansion of e.g.f. tanh(x/(1 - x)).
0
0, 1, 2, 4, 0, -104, -1200, -10352, -68992, -177536, 5310720, 145374208, 2512029696, 33484862464, 294806779904, -1053894275072, -133585065738240, -4148745576218624, -92116699894185984, -1510783598900412416, -11327731683300474880, 414155615537321476096, 25541948643911385219072
OFFSET
0,3
COMMENTS
Lah transform of the sequence 0, 1, 0, -2, 0, 16, 0, -272, ... (A155585 with initial term 0).
LINKS
MAPLE
a:=series(tanh(x/(1 - x)), x=0, 23): seq(n!*coeff(a, x, n), n=0..22); # Paolo P. Lava, Mar 26 2019
MATHEMATICA
nmax = 22; CoefficientList[Series[Tanh[x/(1 - x)], {x, 0, nmax}], x] Range[0, nmax]!
Table[Sum[Binomial[n - 1, k - 1] 2^k EulerE[k, 1] n!/k!, {k, n}], {n, 0, 22}]
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Jul 27 2018
STATUS
approved