Complexity of the decidability of the unquantified set theory with a rank operator

M. Tetruashvili
1994 Georgian Mathematical Journal  
The unquantified set theory MLSR containing the symbols ∪, \, =, ∈, R (R(x) is interpreted as a rank of x) is considered. It is proved that there exists an algorithm which for any formula Q of the MLSR theory decides whether Q is true or not using the space c|Q| 3 (|Q| is the length of Q).
doi:10.1007/bf02317684 fatcat:6ma2zv3u3ngm7oyt2axo3ihrtq