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 A139134 a(n) = n-th derivative of Sec(Exp(z)-1) at z=0. 4

%I

%S 1,0,1,3,12,65,417,3094,26243,250371,2652754,30910935,392895789,

%T 5409783392,80214503397,1274329677391,21594115259540,388790596531173,

%U 7411710847692157,149142571391245758,3159081458947418511

%N a(n) = n-th derivative of Sec(Exp(z)-1) at z=0.

%H Vincenzo Librandi, <a href="/A139134/b139134.txt">Table of n, a(n) for n = 0..100</a>

%F E.G.F. = sec(exp(z)-1)

%F a(n) ~ 2*n!/((2+Pi)*log((2+Pi)/2)^(n+1)). - _Vaclav Kotesovec_, Sep 25 2013

%t Table[D[Sec[Exp[x] - 1], {x, n}] /. x -> 0, {n, 0, 30}]

%Y Cf. A080832.

%K easy,nonn

%O 0,4

%A Richard Chapling (r.chappers(AT)gmail.com), Jun 05 2008

%E Typo in Mathematica program corrected by _Vincenzo Librandi_, Sep 26 2013

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Last modified August 6 00:36 EDT 2021. Contains 346493 sequences. (Running on oeis4.)