cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A081557 Binomial transform of expansion of exp(cosh(x)), A005046.

Original entry on oeis.org

1, 1, 2, 4, 11, 31, 107, 379, 1556, 6556, 31007, 150349, 801341, 4373461, 25853102, 156297964, 1012382291, 6698486371, 47089993967, 337789490599, 2557480572656, 19738202807236, 159928950077327, 1319703681935929, 11382338060040761, 99896787342523081
Offset: 0

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Author

Paul Barry, Mar 22 2003

Keywords

Crossrefs

Cf. A081558.

Programs

  • Magma
    m:=30; R:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!( Exp(Cosh(x)+x-1) )); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, Aug 13 2019
    
  • Maple
    seq(coeff(series(exp(cosh(x)+x-1), x, n+1)*factorial(n), x, n), n = 0 .. 30); # G. C. Greubel, Aug 13 2019
  • Mathematica
    With[{nn = 30}, CoefficientList[Series[Exp[Cosh[x] + x - 1], {x, 0, nn}], x] Range[0, nn]!] (* Vincenzo Librandi, Aug 08 2013 *)
  • PARI
    my(x='x+O('x^30)); Vec(serlaplace( exp(cosh(x)+x-1) )) \\ G. C. Greubel, Aug 13 2019
    
  • Sage
    [factorial(n)*( exp(cosh(x)+x-1) ).series(x,n+1).list()[n] for n in (0..30)] # G. C. Greubel, Aug 13 2019

Formula

E.g.f.: exp(x) * exp(cosh(x)) / e = exp(cosh(x)+x-1).