\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}\frac{1 \cdot {\left(\frac{1}{k}\right)}^{\frac{1}{4}}}{\sqrt{\sqrt{k}}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}double f(double k, double n) {
double r61047 = 1.0;
double r61048 = k;
double r61049 = sqrt(r61048);
double r61050 = r61047 / r61049;
double r61051 = 2.0;
double r61052 = atan2(1.0, 0.0);
double r61053 = r61051 * r61052;
double r61054 = n;
double r61055 = r61053 * r61054;
double r61056 = r61047 - r61048;
double r61057 = r61056 / r61051;
double r61058 = pow(r61055, r61057);
double r61059 = r61050 * r61058;
return r61059;
}
double f(double k, double n) {
double r61060 = 1.0;
double r61061 = 1.0;
double r61062 = k;
double r61063 = r61061 / r61062;
double r61064 = 0.25;
double r61065 = pow(r61063, r61064);
double r61066 = r61060 * r61065;
double r61067 = sqrt(r61062);
double r61068 = sqrt(r61067);
double r61069 = r61066 / r61068;
double r61070 = 2.0;
double r61071 = atan2(1.0, 0.0);
double r61072 = r61070 * r61071;
double r61073 = n;
double r61074 = r61072 * r61073;
double r61075 = r61060 - r61062;
double r61076 = r61075 / r61070;
double r61077 = pow(r61074, r61076);
double r61078 = r61069 * r61077;
return r61078;
}



Bits error versus k



Bits error versus n
Results
Initial program 0.4
rmApplied add-sqr-sqrt0.4
Applied sqrt-prod0.5
Applied associate-/r*0.5
rmApplied add-sqr-sqrt0.5
Applied sqrt-prod0.5
Applied sqrt-prod0.6
Applied add-sqr-sqrt0.6
Applied times-frac0.6
Taylor expanded around 0 0.4
Simplified0.4
Final simplification0.4
herbie shell --seed 2020045 +o rules:numerics
(FPCore (k n)
:name "Migdal et al, Equation (51)"
:precision binary64
(* (/ 1 (sqrt k)) (pow (* (* 2 PI) n) (/ (- 1 k) 2))))