Nuprl Lemma : rel_star-iff-path

[T:Type]. ∀[R:T ⟶ T ⟶ ℙ].  ∀x,y:T.  (x (R^*) ⇐⇒ ∃L:T List. rel-path-between(T;R;x;y;L))


Proof




Definitions occuring in Statement :  rel-path-between: rel-path-between(T;R;x;y;L) list: List rel_star: R^* uall: [x:A]. B[x] prop: infix_ap: y all: x:A. B[x] exists: x:A. B[x] iff: ⇐⇒ Q function: x:A ⟶ B[x] universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] all: x:A. B[x] rel_star: R^* infix_ap: y iff: ⇐⇒ Q and: P ∧ Q implies:  Q exists: x:A. B[x] member: t ∈ T prop: so_lambda: λ2x.t[x] nat: so_apply: x[s] rev_implies:  Q subtype_rel: A ⊆B cand: c∧ B decidable: Dec(P) or: P ∨ Q uimplies: supposing a not: ¬A satisfiable_int_formula: satisfiable_int_formula(fmla) false: False top: Top rel-path-between: rel-path-between(T;R;x;y;L) less_than: a < b squash: T
Lemmas referenced :  rel-path-between_wf exists_wf nat_wf list_wf equal_wf length_wf rel_exp-iff-path rel_exp_wf iff_wf decidable__equal_int full-omega-unsat intformnot_wf intformeq_wf itermVar_wf itermAdd_wf itermSubtract_wf itermConstant_wf int_formula_prop_not_lemma int_formula_prop_eq_lemma int_term_value_var_lemma int_term_value_add_lemma int_term_value_subtract_lemma int_term_value_constant_lemma int_formula_prop_wf subtract_wf decidable__le intformand_wf intformle_wf intformless_wf int_formula_prop_and_lemma int_formula_prop_le_lemma int_formula_prop_less_lemma le_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation lambdaFormation sqequalRule cut independent_pairFormation sqequalHypSubstitution productElimination thin dependent_pairFormation hypothesisEquality hypothesis introduction extract_by_obid isectElimination lambdaEquality productEquality intEquality addEquality setElimination rename natural_numberEquality addLevel independent_functionElimination because_Cache dependent_functionElimination cumulativity applyEquality functionEquality universeEquality unionElimination independent_isectElimination approximateComputation int_eqEquality isect_memberEquality voidElimination voidEquality dependent_set_memberEquality imageElimination

Latex:
\mforall{}[T:Type].  \mforall{}[R:T  {}\mrightarrow{}  T  {}\mrightarrow{}  \mBbbP{}].
    \mforall{}x,y:T.    (x  (R\^{}*)  y  \mLeftarrow{}{}\mRightarrow{}  \mexists{}L:T  List.  rel-path-between(T;R;x;y;L))



Date html generated: 2019_06_20-PM-02_02_11
Last ObjectModification: 2018_08_24-PM-11_36_01

Theory : relations2


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