let Rseq be Function of [:NAT,NAT:],REAL; ( lim_filter ((# Rseq),<.(Frechet_Filter NAT),(Frechet_Filter NAT).)) <> {} implies ex x being Real st lim_filter ((# Rseq),<.(Frechet_Filter NAT),(Frechet_Filter NAT).)) = {x} )
assume A1:
lim_filter ((# Rseq),<.(Frechet_Filter NAT),(Frechet_Filter NAT).)) <> {}
; ex x being Real st lim_filter ((# Rseq),<.(Frechet_Filter NAT),(Frechet_Filter NAT).)) = {x}
reconsider s1 = Rseq as Function of [:NAT,NAT:], the carrier of R^1 ;
consider x being object such that
A2:
lim_filter ((# Rseq),<.(Frechet_Filter NAT),(Frechet_Filter NAT).)) = {x}
by A1, ZFMISC_1:131;
x in lim_filter ((# Rseq),<.(Frechet_Filter NAT),(Frechet_Filter NAT).))
by A2, TARSKI:def 1;
hence
ex x being Real st lim_filter ((# Rseq),<.(Frechet_Filter NAT),(Frechet_Filter NAT).)) = {x}
by A2; verum