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 r62511376 = 2.0;
double r62511377 = t;
double r62511378 = 3.0;
double r62511379 = pow(r62511377, r62511378);
double r62511380 = l;
double r62511381 = r62511380 * r62511380;
double r62511382 = r62511379 / r62511381;
double r62511383 = k;
double r62511384 = sin(r62511383);
double r62511385 = r62511382 * r62511384;
double r62511386 = tan(r62511383);
double r62511387 = r62511385 * r62511386;
double r62511388 = 1.0;
double r62511389 = r62511383 / r62511377;
double r62511390 = pow(r62511389, r62511376);
double r62511391 = r62511388 + r62511390;
double r62511392 = r62511391 - r62511388;
double r62511393 = r62511387 * r62511392;
double r62511394 = r62511376 / r62511393;
return r62511394;
}
herbie shell --seed 2019107 +o rules:numerics
(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))))