let Rseq be Function of [:NAT,NAT:],REAL; ( Rseq is uniformly_convergent_in_cod1 & lim_in_cod1 Rseq is convergent implies ( Rseq is P-convergent & P-lim Rseq = cod1_major_iterated_lim Rseq ) )
assume that
a3:
Rseq is uniformly_convergent_in_cod1
and
a2:
lim_in_cod1 Rseq is convergent
; ( Rseq is P-convergent & P-lim Rseq = cod1_major_iterated_lim Rseq )
a4:
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
|.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| < elet e be
Real;
( 0 < e implies ex N being Nat st
for n, m being Nat st n >= N & m >= N holds
|.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| < e )assume a5:
0 < e
;
ex N being Nat st
for n, m being Nat st n >= N & m >= N holds
|.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| < ethen consider N1 being
Nat such that a6:
for
m being
Nat st
m >= N1 holds
for
n being
Nat holds
|.((Rseq . (n,m)) - ((lim_in_cod1 Rseq) . n)).| < e / 2
by a3;
consider z being
Real such that a7:
for
e being
Real st
e > 0 holds
ex
N2 being
Nat st
for
m being
Nat st
m >= N2 holds
|.(((lim_in_cod1 Rseq) . m) - z).| < e
by a2, SEQ_2:def 6;
a8:
z = cod1_major_iterated_lim Rseq
by a2, a7, def34;
consider N2 being
Nat such that a9:
for
n being
Nat st
n >= N2 holds
|.(((lim_in_cod1 Rseq) . n) - z).| < e / 2
by a5, a7;
set N =
max (
N1,
N2);
a0:
max (
N1,
N2) is
Nat
by TARSKI:1;
for
n,
m being
Nat st
n >= max (
N1,
N2) &
m >= max (
N1,
N2) holds
|.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| < e
proof
let n,
m be
Nat;
( n >= max (N1,N2) & m >= max (N1,N2) implies |.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| < e )
assume a10:
(
n >= max (
N1,
N2) &
m >= max (
N1,
N2) )
;
|.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| < e
(
max (
N1,
N2)
>= N1 &
max (
N1,
N2)
>= N2 )
by XXREAL_0:25;
then
(
n >= N2 &
m >= N1 )
by a10, XXREAL_0:2;
then
(
|.((Rseq . (n,m)) - ((lim_in_cod1 Rseq) . n)).| < e / 2 &
|.(((lim_in_cod1 Rseq) . n) - z).| < e / 2 )
by a6, a9;
then a12:
|.((Rseq . (n,m)) - ((lim_in_cod1 Rseq) . n)).| + |.(((lim_in_cod1 Rseq) . n) - z).| < (e / 2) + (e / 2)
by XREAL_1:8;
|.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| <= |.((Rseq . (n,m)) - ((lim_in_cod1 Rseq) . n)).| + |.(((lim_in_cod1 Rseq) . n) - (cod1_major_iterated_lim Rseq)).|
by COMPLEX1:63;
hence
|.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| < e
by a8, a12, XXREAL_0:2;
verum
end; hence
ex
N being
Nat st
for
n,
m being
Nat st
n >= N &
m >= N holds
|.((Rseq . (n,m)) - (cod1_major_iterated_lim Rseq)).| < e
by a0;
verum end;
hence
Rseq is P-convergent
; P-lim Rseq = cod1_major_iterated_lim Rseq
hence
P-lim Rseq = cod1_major_iterated_lim Rseq
by a4, def6; verum