Nuprl Lemma : null_member

[T:Type]. ∀[L:T List]. ∀[x:T].  ¬(x ∈ L) supposing ↑null(L)


Proof




Definitions occuring in Statement :  l_member: (x ∈ l) null: null(as) list: List assert: b uimplies: supposing a uall: [x:A]. B[x] not: ¬A universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uimplies: supposing a not: ¬A implies:  Q false: False prop:
Lemmas referenced :  assert_elim null_wf member-implies-null-eq-bfalse btrue_neq_bfalse l_member_wf assert_wf list_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut lambdaFormation thin hypothesis lemma_by_obid sqequalHypSubstitution isectElimination hypothesisEquality independent_isectElimination equalityTransitivity equalitySymmetry independent_functionElimination voidElimination sqequalRule lambdaEquality dependent_functionElimination because_Cache isect_memberEquality universeEquality

Latex:
\mforall{}[T:Type].  \mforall{}[L:T  List].  \mforall{}[x:T].    \mneg{}(x  \mmember{}  L)  supposing  \muparrow{}null(L)



Date html generated: 2016_05_14-AM-07_39_34
Last ObjectModification: 2015_12_26-PM-02_13_21

Theory : list_1


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