L = {w#x| w,x ∈ {0, 1}$^*$ and $M_w$ have $BIN^{-1}$(x) different States}
$M_w$ is the encoded Turing machine.
It is definitely decidable, but i need to show a proof for that.
I thought, that i can use a reduction $A ≤ B$ to show if $A$ is decidable then $B$ is also decidable and $A$ is something like
{w#x| w,x ∈ {0, 1}$^*$ and $M_w$ halts for any x after n steps}
. But i could not apply such a solution.