\[\frac{2}{\left(\left(\frac{{t}^{3}}{\ell \cdot \ell} \cdot \sin k\right) \cdot \tan k\right) \cdot \left(\left(1 + {\left(\frac{k}{t}\right)}^{2}\right) + 1\right)}\]

\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 r1852489 = 2.0;
        double r1852490 = t;
        double r1852491 = 3.0;
        double r1852492 = pow(r1852490, r1852491);
        double r1852493 = l;
        double r1852494 = r1852493 * r1852493;
        double r1852495 = r1852492 / r1852494;
        double r1852496 = k;
        double r1852497 = sin(r1852496);
        double r1852498 = r1852495 * r1852497;
        double r1852499 = tan(r1852496);
        double r1852500 = r1852498 * r1852499;
        double r1852501 = 1.0;
        double r1852502 = r1852496 / r1852490;
        double r1852503 = pow(r1852502, r1852489);
        double r1852504 = r1852501 + r1852503;
        double r1852505 = r1852504 + r1852501;
        double r1852506 = r1852500 * r1852505;
        double r1852507 = r1852489 / r1852506;
        return r1852507;
}

Reproduce

herbie shell --seed 2019151 
(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))))

Timeout in 10.0m

Reproduce