A059367 - OEIS

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A059367

From solution to x = tan x (next term is not an integer).

%I #5 Jan 01 2021 10:09:33

%S 1,2,13,146,2343,48984

%N From solution to x = tan x (next term is not an integer).

%C Suppose 1/y = 1/x + arctan(x). Then arctan(x) = Sum_{n>=0} a(n) * y^(2n+1)/(2n+1)!!. Note that a(6) = 6316012/5. a(7) = 38759594. - _Michael Somos_, Jan 01 2021

%D L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 171, #33.

%Y Cf. A079330.

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Jan 28 2001