\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}\frac{1 \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1}{2}\right)}}{\sqrt{k} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}double f(double k, double n) {
double r142312 = 1.0;
double r142313 = k;
double r142314 = sqrt(r142313);
double r142315 = r142312 / r142314;
double r142316 = 2.0;
double r142317 = atan2(1.0, 0.0);
double r142318 = r142316 * r142317;
double r142319 = n;
double r142320 = r142318 * r142319;
double r142321 = r142312 - r142313;
double r142322 = r142321 / r142316;
double r142323 = pow(r142320, r142322);
double r142324 = r142315 * r142323;
return r142324;
}
double f(double k, double n) {
double r142325 = 1.0;
double r142326 = 2.0;
double r142327 = atan2(1.0, 0.0);
double r142328 = r142326 * r142327;
double r142329 = n;
double r142330 = r142328 * r142329;
double r142331 = r142325 / r142326;
double r142332 = pow(r142330, r142331);
double r142333 = r142325 * r142332;
double r142334 = k;
double r142335 = sqrt(r142334);
double r142336 = r142334 / r142326;
double r142337 = pow(r142330, r142336);
double r142338 = r142335 * r142337;
double r142339 = r142333 / r142338;
return r142339;
}



Bits error versus k



Bits error versus n
Results
Initial program 0.6
rmApplied div-sub0.6
Applied pow-sub0.5
Applied frac-times0.4
Final simplification0.4
herbie shell --seed 2020064
(FPCore (k n)
:name "Migdal et al, Equation (51)"
:precision binary64
(* (/ 1 (sqrt k)) (pow (* (* 2 PI) n) (/ (- 1 k) 2))))