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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

%I

%S 1,12,375,22155,2113020,295956045,57148456365,14541025999500,

%T 4712328126180675,1894168782984052575,924528651354021413700,

%U 538492713580088225984025

%N 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.

%H G. C. Greubel, <a href="/A081021/b081021.txt">Table of n, a(n) for n = 1..224</a>

%F 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...

%t 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 *)

%Y Cf. A081020.

%K nonn

%O 1,2

%A _Karol A. Penson_, Mar 01 2003

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Last modified September 16 18:26 EDT 2021. Contains 347473 sequences. (Running on oeis4.)