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commit 05ffb1207d71862521175054f714b84934d35ca5
parent 1c2d0dc44b1240c39828849112f9cb24df36cf6c
Author: Antoine Amarilli <a3nm@a3nm.net>
Date:   Mon, 30 Mar 2026 17:30:35 +0200

commit with codex

Diffstat:
binary_relation | 7+++++++
buchis_theorem | 2+-
equality_generating_dependency | 2++
fo2 | 2+-
fo3 | 7+++++++
fok | 3++-
preorder | 9+++++++++
quantifier | 1+
reflexive_relation | 5+++++
relation | 9+++++++++
satisfiability | 2+-
satisfiability_finite | 10++++++++++
symmetric_relation | 5+++++
transitive_relation | 7+++++++
tseytin_transformation | 2++
15 files changed, 69 insertions(+), 4 deletions(-)

diff --git a/binary_relation b/binary_relation @@ -0,0 +1,7 @@ +# Binary relation + +A [relation] of [arity] two + +Up: [relation] + +See also: [FO2], [unary_relation] diff --git a/buchis_theorem b/buchis_theorem @@ -6,6 +6,6 @@ Equivalence of [monadic_second_order_logic] and of [regular_languages] for [logi Up: [theorem] in [formal_language_theory] -See also: [Büchi_automaton] +See also: [Büchi_automaton], [trakhtenbrot's_theorem] Aliases: Büchi Elgot Trakhtenbrot theorem diff --git a/equality_generating_dependency b/equality_generating_dependency @@ -7,3 +7,5 @@ A [database_dependency] in which the head is an [equality] [atom] Up: [database_dependency], [first_order_logic] Aliases: EGD, EGDs + +See also: [equality_relation] diff --git a/fo2 b/fo2 @@ -6,7 +6,7 @@ extensions: - [c2] with [counting_quantifier] - [gc2] with [guarded_fragment] quantification -FO2 on [words] with order cannot define [successor]: you need [fo3] +FO2 on [words] with order cannot define [successor]: you need [FO3] - with [successor], it defines a variety of [semigroups] Does not enjoy [craig_interpolation], according to [cate2023craig], but enjoys [finite_model_property] diff --git a/fo3 b/fo3 @@ -0,0 +1,7 @@ +# FO3 + +[first_order_logic] with three variables + +Up: [fok] + +See also: [FO2] diff --git a/fok b/fok @@ -6,7 +6,8 @@ Also called "finite variable logics" in the [survey] [grohe1998finite] ## Fragments -- [fo2] +- [FO2] +- [FO3] ## Extensions diff --git a/preorder b/preorder @@ -0,0 +1,9 @@ +# Preorder + +https://en.wikipedia.org/wiki/Preorder + +A [binary_relation] which is [transitive] and [reflexive] but not necessarily [antisymmetric] + +May be [total_relation] or not, if it is total then it is a [total_order] except that there are "ties" + +Up: [ddal_seminar_vincent] diff --git a/quantifier b/quantifier @@ -4,6 +4,7 @@ - [universal_quantifier] - [quantifier_rank] +- [quantifier_prefix] Up: [logic] diff --git a/reflexive_relation b/reflexive_relation @@ -0,0 +1,5 @@ +# Reflexive relation + +A [relation] which satisfies [reflexivity] + +Up: [relation] diff --git a/relation b/relation @@ -1,6 +1,15 @@ # Relation - [equivalence_relation] +- [preorder] - [word_relation] +- [binary_relation] +- [unary_relation] + +Axioms: +- [transitive_relation] +- [reflexive_relation] +- [symmetric_relation] +- [antisymmetric_relation] Up: [mathematics] diff --git a/satisfiability b/satisfiability @@ -10,6 +10,6 @@ The *satisfiability problem* is a [decision_problem] in [logic]: given a [logica Tools: [sat_solver] -See also: [strong_exponential_time_hypothesis], [satisfiability_boolean], [tautology], [automaton_emptiness], [satisfiability_modulo_theory], [equisatisfiability], [enumeration_valuations] +See also: [strong_exponential_time_hypothesis], [satisfiability_boolean], [tautology], [automaton_emptiness], [satisfiability_modulo_theory], [equisatisfiability], [enumeration_valuations], [satisfiability_finite] Up: [computational_problem] diff --git a/satisfiability_finite b/satisfiability_finite @@ -0,0 +1,10 @@ +# Finite satisfiability + +Like [satisfiability] but deciding whether a [logic_formula] has a [finite_model] + +- [finite_model_property] +- [finite_controllability] + +Up: [satisfiability] + +Aliases: finite satisfiability, finsat diff --git a/symmetric_relation b/symmetric_relation @@ -0,0 +1,5 @@ +# Symmetric relation + +A [binary_relation] which is symmetric, i.e., forall x y R(x, y) -> R(y, x) + +Up: [relation] diff --git a/transitive_relation b/transitive_relation @@ -0,0 +1,7 @@ +# Transitive relation + +A [relation] which satisfies [transitivity] + +Up: [transitivity] + +Aliases: transitive relations, transitive diff --git a/tseytin_transformation b/tseytin_transformation @@ -7,3 +7,5 @@ Transform a [Boolean_circuit] into [equisatisfiable] [CNF], by adding some addit Up: [circuit] Aliases: Tseytin transform + +See also: [scott_normal_form]