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

\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)}

(FPCore (v t)
 :precision binary64
 (/
  (- 1.0 (* 5.0 (* v v)))
  (* (* (* PI t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))

double code(double v, double t) {
	return (1.0 - (5.0 * (v * v))) / (((((double) M_PI) * t) * sqrt(2.0 * (1.0 - (3.0 * (v * v))))) * (1.0 - (v * v)));
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2021060 
(FPCore (v t)
  :name "Falkner and Boettcher, Equation (20:1,3)"
  :precision binary64
  (/ (- 1.0 (* 5.0 (* v v))) (* (* (* PI t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))

Backtrace

Failed to produce proof for (.f64 (/.f64 (/.f64 1 (cbrt.f64 PI.f64)) (cbrt.f64 t)) (/.f64 (-.f64 1 (.f64 5 (.f64 v v))) (.f64 (sqrt.f64 (.f64 2 (-.f64 1 (.f64 (.f64 v v) 3)))) (-.f64 1 (.f64 v v))))) to (/.f64 (/.f64 (/.f64 (-.f64 1 (.f64 v (.f64 v 5))) (-.f64 1 (.f64 v v))) (sqrt.f64 (.f64 2 (-.f64 1 (.f64 (.f64 v v) 3))))) (*.f64 (cbrt.f64 t) (cbrt.f64 PI.f64)))		L	C
for-loop	/data/pavpan/nightlies/herbie/egg-generate-proof/src/core/simplify.rkt	167	8
(unnamed)	/data/pavpan/nightlies/herbie/egg-generate-proof/src/core/simplify.rkt	149	6
egraph-add-exprs	/data/pavpan/nightlies/herbie/egg-generate-proof/egg-herbie/main.rkt	154	0
with-egraph	/data/pavpan/nightlies/herbie/egg-generate-proof/egg-herbie/main.rkt	74	0
(unnamed)	/data/pavpan/nightlies/herbie/egg-generate-proof/src/core/simplify.rkt	79	0
simplify!	/data/pavpan/nightlies/herbie/egg-generate-proof/src/mainloop.rkt	236	0
run-iter!	/data/pavpan/nightlies/herbie/egg-generate-proof/src/mainloop.rkt	360	0
run-improve	/data/pavpan/nightlies/herbie/egg-generate-proof/src/mainloop.rkt	377	0
(unnamed)	/data/pavpan/nightlies/herbie/egg-generate-proof/src/sandbox.rkt	54	6
run	/opt/racket-7.9/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk	/opt/racket-7.9/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.9/collects/racket/engine.rkt	42	24