\[\alpha > -1 \land \beta > -1\]

\[\frac{\frac{\frac{\left(\left(\alpha + \beta\right) + \beta \cdot \alpha\right) + 1}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\left(\alpha + \beta\right) + 2 \cdot 1\right) + 1}\]

\frac{\frac{\frac{\left(\left(\alpha + \beta\right) + \beta \cdot \alpha\right) + 1}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\left(\alpha + \beta\right) + 2 \cdot 1\right) + 1}

(FPCore (alpha beta)
 :precision binary64
 (/
  (/
   (/ (+ (+ (+ alpha beta) (* beta alpha)) 1.0) (+ (+ alpha beta) (* 2.0 1.0)))
   (+ (+ alpha beta) (* 2.0 1.0)))
  (+ (+ (+ alpha beta) (* 2.0 1.0)) 1.0)))

double code(double alpha, double beta) {
	return (((((alpha + beta) + (beta * alpha)) + 1.0) / ((alpha + beta) + (2.0 * 1.0))) / ((alpha + beta) + (2.0 * 1.0))) / (((alpha + beta) + (2.0 * 1.0)) + 1.0);
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2021060 
(FPCore (alpha beta)
  :name "Octave 3.8, jcobi/3"
  :precision binary64
  :pre (and (> alpha -1.0) (> beta -1.0))
  (/ (/ (/ (+ (+ (+ alpha beta) (* beta alpha)) 1.0) (+ (+ alpha beta) (* 2.0 1.0))) (+ (+ alpha beta) (* 2.0 1.0))) (+ (+ (+ alpha beta) (* 2.0 1.0)) 1.0)))

Backtrace

Failed to produce proof for (.f64 (/.f64 (.f64 (.f64 (+.f64 beta 1) (+.f64 beta 1)) (+.f64 beta 1)) (.f64 (.f64 (+.f64 alpha (+.f64 beta 2)) (+.f64 alpha (+.f64 beta 2))) (+.f64 alpha (+.f64 beta 2)))) (/.f64 (.f64 (.f64 1 1) 1) (.f64 (.f64 (/.f64 (+.f64 (+.f64 2 beta) alpha) (/.f64 (+.f64 1 alpha) (+.f64 2 (+.f64 1 (+.f64 beta alpha))))) (/.f64 (+.f64 (+.f64 2 beta) alpha) (/.f64 (+.f64 1 alpha) (+.f64 2 (+.f64 1 (+.f64 beta alpha)))))) (/.f64 (+.f64 (+.f64 2 beta) alpha) (/.f64 (+.f64 1 alpha) (+.f64 2 (+.f64 1 (+.f64 beta alpha)))))))) to (/.f64 (/.f64 (pow.f64 (+.f64 1 beta) 3) (pow.f64 (+.f64 alpha (+.f64 2 beta)) 3)) (pow.f64 (.f64 (/.f64 (+.f64 alpha (+.f64 2 beta)) (+.f64 alpha 1)) (+.f64 2 (+.f64 (+.f64 1 beta) alpha))) 3))		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