Nuprl Lemma : null-mapfilter
∀P,f,L:Top.  (null(mapfilter(f;P;L)) ~ null(filter(P;L)))
Proof
Definitions occuring in Statement : 
mapfilter: mapfilter(f;P;L)
, 
null: null(as)
, 
filter: filter(P;l)
, 
top: Top
, 
all: ∀x:A. B[x]
, 
sqequal: s ~ t
Definitions unfolded in proof : 
all: ∀x:A. B[x]
, 
mapfilter: mapfilter(f;P;L)
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
top: Top
Lemmas referenced : 
null-map, 
top_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
cut, 
sqequalRule, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
hypothesis
Latex:
\mforall{}P,f,L:Top.    (null(mapfilter(f;P;L))  \msim{}  null(filter(P;L)))
Date html generated:
2016_05_14-PM-01_29_32
Last ObjectModification:
2015_12_26-PM-05_22_29
Theory : list_1
Home
Index