Simplify() doesn't work for solution to linear system

[zhiyaooooo]

Hello, I want to generate symbolic solution to a 4d linear system. But when I simplify sol[1], it takes an hour and eventually results in a "DivideError: integer division error". This is unexpected because sol[2], sol[3] and sol[4] are simplified in several seconds. All four solutions should have a similar form.

Here is a minimal example:

using Symbolics
A = Symbolics.@variables(A[1:4, 1:4])[1] |> Symbolics.scalarize
b = Symbolics.@variables(b[1:4])[1] |> Symbolics.scalarize
sol = -(A \ b)
Symbolics.simplify(sol[4])
Symbolics.simplify(sol[3])
Symbolics.simplify(sol[2])
Symbolics.simplify(sol[1]) # takes an hour and returns an error

The reason I want to simplify the solution is that 'sol' returns 'NaN' for some values of 'A' and 'b', but the numerical solution '-A\b' can be computed correctly. Simplifying the solution resolves this problem.