Primitive of x by Hyperbolic Secant of a x

Theorem
where $E_{2 n}$ denotes the $2 n$th Euler number.

Also see

 * Primitive of $x \sinh a x$
 * Primitive of $x \cosh a x$
 * Primitive of $x \tanh a x$
 * Primitive of $x \coth a x$
 * Primitive of $x \csch a x$