Nuprl Lemma : singleton-type-product

[A,B:Type].  (singleton-type(A)  singleton-type(B)  singleton-type(A × B))


Proof




Definitions occuring in Statement :  singleton-type: singleton-type(A) uall: [x:A]. B[x] implies:  Q product: x:A × B[x] universe: Type
Definitions unfolded in proof :  singleton-type: singleton-type(A) uall: [x:A]. B[x] implies:  Q exists: x:A. B[x] member: t ∈ T all: x:A. B[x] prop: so_lambda: λ2x.t[x] so_apply: x[s] guard: {T}
Lemmas referenced :  all_wf equal_wf exists_wf
Rules used in proof :  sqequalSubstitution sqequalRule sqequalReflexivity sqequalTransitivity computationStep isect_memberFormation lambdaFormation sqequalHypSubstitution productElimination thin rename dependent_pairFormation independent_pairEquality hypothesisEquality cut hypothesis productEquality lemma_by_obid isectElimination lambdaEquality universeEquality dependent_functionElimination

Latex:
\mforall{}[A,B:Type].    (singleton-type(A)  {}\mRightarrow{}  singleton-type(B)  {}\mRightarrow{}  singleton-type(A  \mtimes{}  B))



Date html generated: 2016_05_14-PM-04_02_10
Last ObjectModification: 2015_12_26-PM-07_43_05

Theory : equipollence!!cardinality!


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