\[\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}\]

\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}

double f(double v, double t) {
        double r72716 = 1.0;
        double r72717 = 5.0;
        double r72718 = v;
        double r72719 = r72718 * r72718;
        double r72720 = r72717 * r72719;
        double r72721 = r72716 - r72720;
        double r72722 = atan2(1.0, 0.0);
        double r72723 = t;
        double r72724 = r72722 * r72723;
        double r72725 = 2.0;
        double r72726 = 3.0;
        double r72727 = r72726 * r72719;
        double r72728 = r72716 - r72727;
        double r72729 = r72725 * r72728;
        double r72730 = sqrt(r72729);
        double r72731 = r72724 * r72730;
        double r72732 = r72716 - r72719;
        double r72733 = r72731 * r72732;
        double r72734 = r72721 / r72733;
        return r72734;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019195 
(FPCore (v t)
  :name "Falkner and Boettcher, Equation (20:1,3)"
  (/ (- 1.0 (* 5.0 (* v v))) (* (* (* PI t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))

Backtrace

get-representation: Unknown representation #f		L	C
(unnamed)	/data/pavpan/nightlies/herbie/various-cleanup/src/core/localize.rkt	23	13
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
map	/opt/racket-7.0/collects/racket/private/map.rkt	35	13
parse-loop30	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
map	/opt/racket-7.0/collects/racket/private/map.rkt	35	13
parse-loop30	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
map	/opt/racket-7.0/collects/racket/private/map.rkt	35	13
parse-loop30	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
map	/opt/racket-7.0/collects/racket/private/map.rkt	35	13
parse-loop30	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
localize-error	/data/pavpan/nightlies/herbie/various-cleanup/src/core/localize.rkt	61	0
localize!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	123	0
run-iter!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	323	0
for-loop	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	359	4
run-improve47	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	342	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28
run	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28