?

\[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]

(FPCore (k n)
 :precision binary64
 (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))

double code(double k, double n) {
	return (1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0));
}

public static double code(double k, double n) {
	return (1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0));
}

def code(k, n):
	return (1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))

function code(k, n)
	return Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0)))
end

function tmp = code(k, n)
	tmp = (1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0));
end

code[k_, n_] := N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[Power[N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]

\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}

Reproduce?

Please include this information when filing a bug report:

herbie shell --seed 2023033 
(FPCore (k n)
  :name "Migdal et al, Equation (51)"
  :precision binary64
  (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))

Backtrace

map: contract violation expected: list? given: #<eof>		L	C
gen-map	/usr/share/racket/collects/racket/private/map.rkt	257	2
run-egglog	/home/nightlies/herbie/oflatt-egglog-ctx/src/egglog/run-egglog.rkt	1456	0
run-simplify-input	/home/nightlies/herbie/oflatt-egglog-ctx/src/core/simplify.rkt	73	0
simplify-batch	/home/nightlies/herbie/oflatt-egglog-ctx/src/core/simplify.rkt	48	0
(unnamed)	/usr/share/racket/collects/racket/contract/private/arrow-higher-order.rkt	379	33
simplify!	/home/nightlies/herbie/oflatt-egglog-ctx/src/patch.rkt	246	0
patch-table-run	/home/nightlies/herbie/oflatt-egglog-ctx/src/patch.rkt	318	0
(unnamed)	/usr/share/racket/collects/racket/contract/private/arrow-val-first.rkt	486	18
run-iter!	/home/nightlies/herbie/oflatt-egglog-ctx/src/mainloop.rkt	262	0
mutate!	/home/nightlies/herbie/oflatt-egglog-ctx/src/mainloop.rkt	372	0
run-improve!	/home/nightlies/herbie/oflatt-egglog-ctx/src/mainloop.rkt	320	0
run-herbie	/home/nightlies/herbie/oflatt-egglog-ctx/src/sandbox.rkt	57	0
(unnamed)	/home/nightlies/herbie/oflatt-egglog-ctx/src/sandbox.rkt	133	6
(unnamed)	/usr/share/racket/pkgs/profile-lib/main.rkt	40	10
profile-thunk	/usr/share/racket/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/usr/share/racket/collects/racket/engine.rkt	42	24