\[\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}\]
\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}
double f(double x) {
        double r24832 = 2.0;
        double r24833 = x;
        double r24834 = r24832 * r24833;
        double r24835 = exp(r24834);
        double r24836 = 1.0;
        double r24837 = r24835 - r24836;
        double r24838 = exp(r24833);
        double r24839 = r24838 - r24836;
        double r24840 = r24837 / r24839;
        double r24841 = sqrt(r24840);
        return r24841;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019323 
(FPCore (x)
  :name "sqrtexp (problem 3.4.4)"
  :precision binary64
  (sqrt (/ (- (exp (* 2 x)) 1) (- (exp x) 1))))

Backtrace

dict-ref: no value for key: 'branch24831 in: '((x . binary64))LC
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/points.rkt1064
make-sampler/data/pavpan/nightlies/herbie/fix-interface-bugs/src/points.rkt990
prepare-points-intervals/data/pavpan/nightlies/herbie/fix-interface-bugs/src/points.rkt1210
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt2339
sindices->spoints/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt1940
f33/opt/racket-7.2/collects/racket/match/compiler.rkt50740
get-final-combination/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3690
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128
run/opt/racket-7.2/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.2/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128