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A081021 Even order Taylor coefficients at x = 0 of exp( (sqrt(2)-sqrt(-2*x^2+2))/(-2*x^2+2)^(1/2) ), odd order coefficients being equal to zero. 2
1, 12, 375, 22155, 2113020, 295956045, 57148456365, 14541025999500, 4712328126180675, 1894168782984052575, 924528651354021413700, 538492713580088225984025 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..224

FORMULA

In Maple notation: a(n)=subs(x=0, diff(exp((sqrt(2)-sqrt(-2*x^2+2))/(-2*x^2+2)^(1/2), x$2*n)), n=1, 2...

MATHEMATICA

Rest[With[{nmax = 100}, CoefficientList[Series[Exp[(Sqrt[2] - Sqrt[2 - 2*x^2])/(Sqrt[2 - 2*x^2]) ], {x, 0, nmax}], x]*Range[0, nmax]!][[1 ;; -1 ;; 2]]] (* G. C. Greubel, Sep 11 2018 *)

CROSSREFS

Cf. A081020.

Sequence in context: A235685 A024298 A177112 * A269609 A251590 A196459

Adjacent sequences:  A081018 A081019 A081020 * A081022 A081023 A081024

KEYWORD

nonn

AUTHOR

Karol A. Penson, Mar 01 2003

STATUS

approved

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Last modified October 15 07:55 EDT 2019. Contains 328026 sequences. (Running on oeis4.)