\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 r147876 = 1.0;
double r147877 = k;
double r147878 = sqrt(r147877);
double r147879 = r147876 / r147878;
double r147880 = 2.0;
double r147881 = atan2(1.0, 0.0);
double r147882 = r147880 * r147881;
double r147883 = n;
double r147884 = r147882 * r147883;
double r147885 = r147876 - r147877;
double r147886 = r147885 / r147880;
double r147887 = pow(r147884, r147886);
double r147888 = r147879 * r147887;
return r147888;
}
double f(double k, double n) {
double r147889 = 1.0;
double r147890 = 1.0;
double r147891 = k;
double r147892 = r147890 / r147891;
double r147893 = 0.25;
double r147894 = pow(r147892, r147893);
double r147895 = r147889 * r147894;
double r147896 = sqrt(r147891);
double r147897 = sqrt(r147896);
double r147898 = r147895 / r147897;
double r147899 = 2.0;
double r147900 = atan2(1.0, 0.0);
double r147901 = r147899 * r147900;
double r147902 = n;
double r147903 = r147901 * r147902;
double r147904 = r147889 - r147891;
double r147905 = r147904 / r147899;
double r147906 = pow(r147903, r147905);
double r147907 = r147898 * r147906;
return r147907;
}



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
Taylor expanded around 0 0.4
Final simplification0.4
herbie shell --seed 2020042
(FPCore (k n)
:name "Migdal et al, Equation (51)"
:precision binary64
(* (/ 1 (sqrt k)) (pow (* (* 2 PI) n) (/ (- 1 k) 2))))