let T be non empty TopSpace; :: thesis: for s being sequence of the carrier of T
for x being Point of T
for B being basis of (BOOL2F (NeighborhoodSystem x)) holds
( x in lim_f s iff for b being Element of B ex i being Element of OrderedNAT st
for j being Element of OrderedNAT st i <= j holds
s . j in b )

let s be sequence of the carrier of T; :: thesis: for x being Point of T
for B being basis of (BOOL2F (NeighborhoodSystem x)) holds
( x in lim_f s iff for b being Element of B ex i being Element of OrderedNAT st
for j being Element of OrderedNAT st i <= j holds
s . j in b )

let x be Point of T; :: thesis: for B being basis of (BOOL2F (NeighborhoodSystem x)) holds
( x in lim_f s iff for b being Element of B ex i being Element of OrderedNAT st
for j being Element of OrderedNAT st i <= j holds
s . j in b )

let B be basis of (BOOL2F (NeighborhoodSystem x)); :: thesis: ( x in lim_f s iff for b being Element of B ex i being Element of OrderedNAT st
for j being Element of OrderedNAT st i <= j holds
s . j in b )

( x in lim_filter (s,(Frechet_Filter NAT)) iff for b being Element of B ex i being Element of OrderedNAT st
for j being Element of OrderedNAT st i <= j holds
s . j in b ) by Th41;
hence ( x in lim_f s iff for b being Element of B ex i being Element of OrderedNAT st
for j being Element of OrderedNAT st i <= j holds
s . j in b ) ; :: thesis: verum