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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 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.)