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A317410
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Expansion of e.g.f. sec(x/(1 - x)).
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1
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1, 0, 1, 6, 41, 340, 3361, 38682, 508241, 7506504, 123108961, 2219822990, 43648348985, 929502984540, 21311829302401, 523455901397730, 13712375005949345, 381621247702458640, 11244620308691664961, 349715433597469496982, 11448372539225223596105, 393503844330372123056100, 14169282835811140260616801
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OFFSET
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0,4
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COMMENTS
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Lah transform of the sequence 1, 0, 1, 0, 5, 0, 61, 0, 1385, ... (A000364 interspersed with zeros).
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LINKS
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FORMULA
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E.g.f.: sec(x/(1 - x)).
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MAPLE
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a:=series(sec(x/(1 - x)), x=0, 23): seq(n!*coeff(a, x, n), n=0..22); # Paolo P. Lava, Mar 26 2019
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MATHEMATICA
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nmax = 22; CoefficientList[Series[Sec[x/(1 - x)], {x, 0, nmax}], x] Range[0, nmax]!
Table[Sum[Binomial[n - 1, k - 1] Abs[EulerE[k]] n!/k!, {k, 0, n}], {n, 0, 22}]
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PROG
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(PARI) x = 'x + O('x^30); Vec(serlaplace(1/cos(x/(1 - x)))) \\ Michel Marcus, Jul 28 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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