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0,5
Table of n, a(n) for n=0..26.
E.g.f.: (1/Q(0)-Q(0))/2, where Q(k) = 1 - x/( 2*k+1 + x/Q(k+1) ); (continued fraction). - Sergei N. Gladkovskii, Dec 20 2013
Sinh[ Log[ 1+Tanh[ x ] ] ]
Cf. A009126.
Sequence in context: A223585 A202680 A263568 * A232839 A140299 A119007
Adjacent sequences: A009567 A009568 A009569 * A009571 A009572 A009573
sign,easy
R. H. Hardin
Extended with signs by Olivier Gérard, Mar 15 1997
approved