\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}\frac{\frac{{\left(n \cdot 2\right)}^{\left(\frac{1}{2} - \frac{k}{2}\right)}}{\frac{1}{{\left(\sqrt{\pi}\right)}^{\left(\frac{1}{2} - \frac{k}{2}\right)}}}}{\frac{\sqrt{k}}{{\left(\sqrt{\pi}\right)}^{\left(\frac{1}{2} - \frac{k}{2}\right)}}}double f(double k, double n) {
double r3399612 = 1.0;
double r3399613 = k;
double r3399614 = sqrt(r3399613);
double r3399615 = r3399612 / r3399614;
double r3399616 = 2.0;
double r3399617 = atan2(1.0, 0.0);
double r3399618 = r3399616 * r3399617;
double r3399619 = n;
double r3399620 = r3399618 * r3399619;
double r3399621 = r3399612 - r3399613;
double r3399622 = r3399621 / r3399616;
double r3399623 = pow(r3399620, r3399622);
double r3399624 = r3399615 * r3399623;
return r3399624;
}
double f(double k, double n) {
double r3399625 = n;
double r3399626 = 2.0;
double r3399627 = r3399625 * r3399626;
double r3399628 = 0.5;
double r3399629 = k;
double r3399630 = r3399629 / r3399626;
double r3399631 = r3399628 - r3399630;
double r3399632 = pow(r3399627, r3399631);
double r3399633 = 1.0;
double r3399634 = atan2(1.0, 0.0);
double r3399635 = sqrt(r3399634);
double r3399636 = pow(r3399635, r3399631);
double r3399637 = r3399633 / r3399636;
double r3399638 = r3399632 / r3399637;
double r3399639 = sqrt(r3399629);
double r3399640 = r3399639 / r3399636;
double r3399641 = r3399638 / r3399640;
return r3399641;
}



Bits error versus k



Bits error versus n
Results
Initial program 0.4
Simplified0.3
rmApplied unpow-prod-down0.5
Applied associate-/l*0.5
rmApplied add-sqr-sqrt0.5
Applied unpow-prod-down0.4
Applied *-un-lft-identity0.4
Applied times-frac0.4
Applied associate-/r*0.4
Final simplification0.4
herbie shell --seed 2019153
(FPCore (k n)
:name "Migdal et al, Equation (51)"
(* (/ 1 (sqrt k)) (pow (* (* 2 PI) n) (/ (- 1 k) 2))))