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A347070 E.g.f.: (sec(x) - tan(x)) / (2 - exp(x)). 0
1, 0, 2, 5, 38, 245, 2232, 22045, 256958, 3321945, 48017612, 761377685, 13186155578, 247266049745, 4994576392392, 108081289248925, 2494888781667398, 61188799954637145, 1588986391492725572, 43555979938733393765, 1256760600183277906418, 38075558970632725450145 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Inverse boustrophedon transform of Fubini numbers.

LINKS

Table of n, a(n) for n=0..21.

Index entries for sequences related to boustrophedon transform

FORMULA

a(n) = Sum_{k=0..n} (-1)^(n-k) * binomial(n,k) * A000670(k) * A000111(n-k).

a(n) ~ n! * (1 - sin(log(2))) / (2 * cos(log(2)) * log(2)^(n+1)). - Vaclav Kotesovec, Aug 23 2021

MATHEMATICA

nmax = 21; CoefficientList[Series[(Sec[x] - Tan[x])/(2 - Exp[x]), {x, 0, nmax}], x] Range[0, nmax]!

t[n_, 0] := Sum[StirlingS2[n, k] k!, {k, 0, n}]; t[n_, k_] := t[n, k] = t[n, k - 1] - t[n - 1, n - k]; a[n_] := t[n, n]; Table[a[n], {n, 0, 21}]

CROSSREFS

Cf. A000111, A000670, A306857, A337447.

Sequence in context: A036780 A051501 A221681 * A290711 A228837 A206155

Adjacent sequences: A347067 A347068 A347069 * A347071 A347072 A347073

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Aug 15 2021

STATUS

approved

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Last modified November 29 10:31 EST 2022. Contains 358424 sequences. (Running on oeis4.)