let r be Element of REAL ; P-lim ([:NAT,NAT:] --> r) = r
set Rseq = [:NAT,NAT:] --> r;
a1:
for n, m being Nat holds ([:NAT,NAT:] --> r) . (n,m) = r
now for e being Real st 0 < e holds
ex N being Nat st
for n, m being Nat st n >= N & m >= N holds
|.((([:NAT,NAT:] --> r) . (n,m)) - r).| < elet e be
Real;
( 0 < e implies ex N being Nat st
for n, m being Nat st n >= N & m >= N holds
|.((([:NAT,NAT:] --> r) . (n,m)) - r).| < e )assume a2:
0 < e
;
ex N being Nat st
for n, m being Nat st n >= N & m >= N holds
|.((([:NAT,NAT:] --> r) . (n,m)) - r).| < ea4:
now for n, m being Nat st n >= 0 & m >= 0 holds
|.((([:NAT,NAT:] --> r) . (n,m)) - r).| < elet n,
m be
Nat;
( n >= 0 & m >= 0 implies |.((([:NAT,NAT:] --> r) . (n,m)) - r).| < e )assume
(
n >= 0 &
m >= 0 )
;
|.((([:NAT,NAT:] --> r) . (n,m)) - r).| < e
([:NAT,NAT:] --> r) . (
n,
m)
= r
by a1;
hence
|.((([:NAT,NAT:] --> r) . (n,m)) - r).| < e
by a2, COMPLEX1:44;
verum end; reconsider N =
0 as
Nat ;
take N =
N;
for n, m being Nat st n >= N & m >= N holds
|.((([:NAT,NAT:] --> r) . (n,m)) - r).| < ethus
for
n,
m being
Nat st
n >= N &
m >= N holds
|.((([:NAT,NAT:] --> r) . (n,m)) - r).| < e
by a4;
verum end;
hence
P-lim ([:NAT,NAT:] --> r) = r
by def6; verum