Nuprl Lemma : decidable-exists-int_seg-subtype

[i:ℤ]. ∀[j:{i 1...}]. ∀[P:{i..j-} ⟶ ℙ].  Dec(∃k:{i 1..j-}. P[k]) ⊆Dec(∃k:{i..j-}. P[k]) supposing ¬P[i]


Proof




Definitions occuring in Statement :  int_upper: {i...} int_seg: {i..j-} decidable: Dec(P) uimplies: supposing a subtype_rel: A ⊆B uall: [x:A]. B[x] prop: so_apply: x[s] exists: x:A. B[x] not: ¬A function: x:A ⟶ B[x] add: m natural_number: $n int:
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uimplies: supposing a int_upper: {i...} so_lambda: λ2x.t[x] so_apply: x[s] subtype_rel: A ⊆B exists: x:A. B[x] int_seg: {i..j-} lelt: i ≤ j < k and: P ∧ Q le: A ≤ B all: x:A. B[x] decidable: Dec(P) or: P ∨ Q iff: ⇐⇒ Q not: ¬A rev_implies:  Q implies:  Q false: False prop: uiff: uiff(P;Q) subtract: m less_than': less_than'(a;b) true: True top: Top sq_type: SQType(T) guard: {T}
Lemmas referenced :  decidable-subtype exists_wf int_seg_wf decidable__le false_wf not-le-2 condition-implies-le minus-add minus-one-mul add-swap minus-one-mul-top add-commutes add_functionality_wrt_le add-associates le-add-cancel and_wf le_wf less_than_wf not_wf le_reflexive decidable__lt not-lt-2 int_upper_wf decidable__int_equal not-equal-2 zero-add le-add-cancel2 subtype_base_sq int_subtype_base
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut lemma_by_obid sqequalHypSubstitution isectElimination thin addEquality hypothesisEquality natural_numberEquality setElimination rename hypothesis sqequalRule lambdaEquality applyEquality because_Cache independent_isectElimination productElimination dependent_pairEquality dependent_set_memberEquality independent_pairFormation dependent_functionElimination unionElimination lambdaFormation voidElimination independent_functionElimination minusEquality dependent_pairFormation axiomEquality isect_memberEquality equalityTransitivity equalitySymmetry functionEquality cumulativity universeEquality voidEquality intEquality instantiate

Latex:
\mforall{}[i:\mBbbZ{}].  \mforall{}[j:\{i  +  1...\}].  \mforall{}[P:\{i..j\msupminus{}\}  {}\mrightarrow{}  \mBbbP{}].
    Dec(\mexists{}k:\{i  +  1..j\msupminus{}\}.  P[k])  \msubseteq{}r  Dec(\mexists{}k:\{i..j\msupminus{}\}.  P[k])  supposing  \mneg{}P[i]



Date html generated: 2016_05_13-PM-03_47_38
Last ObjectModification: 2015_12_26-AM-09_58_39

Theory : call!by!value_2


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