let a be real number ; :: thesis: ex s being Rational_Sequence st
( s is convergent & lim s = a & ( for n being Element of NAT holds s . n >= a ) )

deffunc H1( Element of NAT ) -> Element of REAL = [/(($1 + 1) * a)\] / ($1 + 1);
consider s being Real_Sequence such that
A1: for n being Element of NAT holds s . n = H1(n) from SEQ_1:sch 1();
now
let n be Element of NAT ; :: thesis: s . n is Rational
[/((n + 1) * a)\] / (n + 1) = s . n by A1;
hence s . n is Rational ; :: thesis: verum
end;
then reconsider s = s as Rational_Sequence by Def6;
take s ; :: thesis: ( s is convergent & lim s = a & ( for n being Element of NAT holds s . n >= a ) )
a in REAL by XREAL_0:def 1;
then reconsider s1 = NAT --> a as Real_Sequence by FUNCOP_1:57;
deffunc H2( Element of NAT ) -> Element of REAL = 1 / ($1 + 1);
consider s2 being Real_Sequence such that
A2: for n being Element of NAT holds s2 . n = H2(n) from SEQ_1:sch 1();
A3: ( s2 is convergent & lim s2 = 0 ) by A2, SEQ_4:45;
set s3 = s1 + s2;
A5: s1 + s2 is convergent by A3, SEQ_2:19;
A6: lim (s1 + s2) = (s1 . 0 ) + 0 by A3, SEQ_4:59
.= a by FUNCOP_1:13 ;
A7: lim s1 = s1 . 0 by SEQ_4:41
.= a by FUNCOP_1:13 ;
A8: now
let n be Element of NAT ; :: thesis: ( s1 . n <= s . n & s . n <= (s1 + s2) . n )
[/((n + 1) * a)\] >= (n + 1) * a by INT_1:def 5;
then [/((n + 1) * a)\] * ((n + 1) " ) >= (a * (n + 1)) * ((n + 1) " ) by XREAL_1:66;
then [/((n + 1) * a)\] * ((n + 1) " ) >= a * ((n + 1) * ((n + 1) " )) ;
then [/((n + 1) * a)\] * ((n + 1) " ) >= a * 1 by XCMPLX_0:def 7;
then [/((n + 1) * a)\] / (n + 1) >= a ;
then A9: [/((n + 1) * a)\] / (n + 1) >= s1 . n by FUNCOP_1:13;
((n + 1) * a) + 1 >= [/((n + 1) * a)\] by INT_1:def 5;
then (((n + 1) * a) + 1) * ((n + 1) " ) >= [/((n + 1) * a)\] * ((n + 1) " ) by XREAL_1:66;
then (((n + 1) * a) + 1) * ((n + 1) " ) >= [/((n + 1) * a)\] / (n + 1) ;
then (((n + 1) * a) + 1) * ((n + 1) " ) >= s . n by A1;
then (((n + 1) * a) + 1) / (n + 1) >= s . n ;
then (((n + 1) * a) / (n + 1)) + (1 / (n + 1)) >= s . n ;
then ((a / (n + 1)) * (n + 1)) + (1 / (n + 1)) >= s . n ;
then a + (1 / (n + 1)) >= s . n by XCMPLX_1:88;
then (s1 . n) + (1 / (n + 1)) >= s . n by FUNCOP_1:13;
then (s1 . n) + (s2 . n) >= s . n by A2;
hence ( s1 . n <= s . n & s . n <= (s1 + s2) . n ) by A1, A9, SEQ_1:11; :: thesis: verum
end;
hence s is convergent by A5, A6, A7, SEQ_2:33; :: thesis: ( lim s = a & ( for n being Element of NAT holds s . n >= a ) )
thus lim s = a by A5, A6, A7, A8, SEQ_2:34; :: thesis: for n being Element of NAT holds s . n >= a
let n be Element of NAT ; :: thesis: s . n >= a
s . n >= s1 . n by A8;
hence s . n >= a by FUNCOP_1:13; :: thesis: verum