Metamath Proof Explorer


Theorem esumfsupre

Description: Formulating an extended sum over integers using the recursive sequence builder. This version is limited to real-valued functions. (Contributed by Thierry Arnoux, 19-Oct-2017)

Ref Expression
Hypothesis esumfsup.1 _kF
Assertion esumfsupre F:0+∞*kFk=supranseq1+F*<

Proof

Step Hyp Ref Expression
1 esumfsup.1 _kF
2 icossicc 0+∞0+∞
3 fss F:0+∞0+∞0+∞F:0+∞
4 2 3 mpan2 F:0+∞F:0+∞
5 1 esumfsup F:0+∞*kFk=supranseq1+𝑒F*<
6 4 5 syl F:0+∞*kFk=supranseq1+𝑒F*<
7 1zzd F:0+∞1
8 elnnuz xx1
9 ffvelcdm F:0+∞xFx0+∞
10 8 9 sylan2br F:0+∞x1Fx0+∞
11 ge0addcl x0+∞y0+∞x+y0+∞
12 11 adantl F:0+∞x0+∞y0+∞x+y0+∞
13 rge0ssre 0+∞
14 simprl F:0+∞x0+∞y0+∞x0+∞
15 13 14 sselid F:0+∞x0+∞y0+∞x
16 simprr F:0+∞x0+∞y0+∞y0+∞
17 13 16 sselid F:0+∞x0+∞y0+∞y
18 rexadd xyx+𝑒y=x+y
19 18 eqcomd xyx+y=x+𝑒y
20 15 17 19 syl2anc F:0+∞x0+∞y0+∞x+y=x+𝑒y
21 7 10 12 20 seqfeq3 F:0+∞seq1+F=seq1+𝑒F
22 21 rneqd F:0+∞ranseq1+F=ranseq1+𝑒F
23 22 supeq1d F:0+∞supranseq1+F*<=supranseq1+𝑒F*<
24 6 23 eqtr4d F:0+∞*kFk=supranseq1+F*<