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

\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 r52704083 = 2.0;
        double r52704084 = t;
        double r52704085 = 3.0;
        double r52704086 = pow(r52704084, r52704085);
        double r52704087 = l;
        double r52704088 = r52704087 * r52704087;
        double r52704089 = r52704086 / r52704088;
        double r52704090 = k;
        double r52704091 = sin(r52704090);
        double r52704092 = r52704089 * r52704091;
        double r52704093 = tan(r52704090);
        double r52704094 = r52704092 * r52704093;
        double r52704095 = 1.0;
        double r52704096 = r52704090 / r52704084;
        double r52704097 = pow(r52704096, r52704083);
        double r52704098 = r52704095 + r52704097;
        double r52704099 = r52704098 + r52704095;
        double r52704100 = r52704094 * r52704099;
        double r52704101 = r52704083 / r52704100;
        return r52704101;
}

Reproduce

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))))

Timeout in 10.0m

Reproduce