Primitive of Hyperbolic Secant of a x over x

Theorem
where $E_k$ denotes the $k$th Euler number.

Also see

 * Primitive of $\dfrac {\sinh a x} x$


 * Primitive of $\dfrac {\cosh a x} x$


 * Primitive of $\dfrac {\tanh a x} x$


 * Primitive of $\dfrac {\coth a x} x$


 * Primitive of $\dfrac {\csch a x} x$