Use the --timeout flag to change the timeout.
\frac{2}{\left(\left(\frac{{t}^{3}}{\ell \cdot \ell} \cdot \sin k\right) \cdot \tan k\right) \cdot \left(\left(1 + {\left(\frac{k}{t}\right)}^{2}\right) - 1\right)}double f(double t, double l, double k) {
double r68984731 = 2.0;
double r68984732 = t;
double r68984733 = 3.0;
double r68984734 = pow(r68984732, r68984733);
double r68984735 = l;
double r68984736 = r68984735 * r68984735;
double r68984737 = r68984734 / r68984736;
double r68984738 = k;
double r68984739 = sin(r68984738);
double r68984740 = r68984737 * r68984739;
double r68984741 = tan(r68984738);
double r68984742 = r68984740 * r68984741;
double r68984743 = 1.0;
double r68984744 = r68984738 / r68984732;
double r68984745 = pow(r68984744, r68984731);
double r68984746 = r68984743 + r68984745;
double r68984747 = r68984746 - r68984743;
double r68984748 = r68984742 * r68984747;
double r68984749 = r68984731 / r68984748;
return r68984749;
}
herbie shell --seed 2019119
(FPCore (t l k)
:name "Toniolo and Linder, Equation (10-)"
(/ 2 (* (* (* (/ (pow t 3) (* l l)) (sin k)) (tan k)) (- (+ 1 (pow (/ k t) 2)) 1))))