fo2 (368B)
1 # Fo2 2 3 [FOk] with two variables 4 5 extensions: 6 - [c2] with [counting_quantifier] 7 - [gc2] with [guarded_fragment] quantification 8 9 FO2 on [words] with order cannot define [successor]: you need [fo3] 10 - with [successor], it defines a variety of [semigroups] 11 12 Does not enjoy [craig_interpolation], according to [cate2023craig], but enjoys [finite_model_property] 13 14 Up: [fok]