Nuprl Lemma : multiply_nat_plus_iff

[i:ℕ+]. ∀[x:ℤ].  (i x ∈ ℕ ⇐⇒ x ∈ ℕ)


Proof




Definitions occuring in Statement :  nat_plus: + nat: uall: [x:A]. B[x] iff: ⇐⇒ Q member: t ∈ T multiply: m int:
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T iff: ⇐⇒ Q and: P ∧ Q implies:  Q subtype_rel: A ⊆B nat_plus: + so_lambda: λ2x.t[x] so_apply: x[s] uimplies: supposing a rev_implies:  Q nat: all: x:A. B[x] decidable: Dec(P) or: P ∨ Q sq_type: SQType(T) guard: {T} exists: x:A. B[x] top: Top ge: i ≥  subtract: m uiff: uiff(P;Q) less_than: a < b squash: T less_than': less_than'(a;b) true: True le: A ≤ B not: ¬A false: False
Lemmas referenced :  istype-nat int_subtype_base set_subtype_base less_than_wf mul_bounds_1a nat_plus_subtype_nat istype-le istype-int nat_plus_wf nat_plus_properties nat_properties decidable__le mul_bounds_1b istype-less_than minus-one-mul subtract_wf subtype_base_sq istype-sqequal le_weakening2 mul-swap istype-void add_functionality_wrt_le le_reflexive minus-one-mul-top zero-add one-mul add-mul-special add-associates two-mul add-commutes mul-distributes-right zero-mul less-iff-le mul-associates add-swap add-zero omega-shadow not-lt-2 minus-zero not-le-2 istype-false decidable__lt
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity Error :isect_memberFormation_alt,  introduction cut independent_pairFormation Error :lambdaFormation_alt,  sqequalHypSubstitution hypothesis sqequalRule Error :equalityIstype,  extract_by_obid baseApply closedConclusion baseClosed hypothesisEquality applyEquality isectElimination thin intEquality Error :lambdaEquality_alt,  natural_numberEquality Error :inhabitedIsType,  independent_isectElimination because_Cache sqequalBase equalitySymmetry Error :dependent_set_memberEquality_alt,  multiplyEquality setElimination rename equalityTransitivity productElimination independent_pairEquality dependent_functionElimination axiomEquality Error :functionIsTypeImplies,  Error :isect_memberEquality_alt,  Error :isectIsTypeImplies,  Error :universeIsType,  applyLambdaEquality unionElimination minusEquality addEquality instantiate cumulativity independent_functionElimination Error :dependent_pairFormation_alt,  promote_hyp voidElimination imageMemberEquality

Latex:
\mforall{}[i:\mBbbN{}\msupplus{}].  \mforall{}[x:\mBbbZ{}].    (i  *  x  \mmember{}  \mBbbN{}  \mLeftarrow{}{}\mRightarrow{}  x  \mmember{}  \mBbbN{})



Date html generated: 2019_06_20-AM-11_26_47
Last ObjectModification: 2018_12_11-PM-01_01_39

Theory : arithmetic


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