Metamath Proof Explorer


Theorem fvffz0

Description: The function value of a function from a finite interval of nonnegative integers. (Contributed by AV, 13-Feb-2021)

Ref Expression
Assertion fvffz0 N 0 I 0 I < N P : 0 N V P I V

Proof

Step Hyp Ref Expression
1 simpr N 0 I 0 I < N P : 0 N V P : 0 N V
2 simp2 N 0 I 0 I < N I 0
3 simp1 N 0 I 0 I < N N 0
4 nn0re I 0 I
5 nn0re N 0 N
6 ltle I N I < N I N
7 4 5 6 syl2anr N 0 I 0 I < N I N
8 7 3impia N 0 I 0 I < N I N
9 elfz2nn0 I 0 N I 0 N 0 I N
10 2 3 8 9 syl3anbrc N 0 I 0 I < N I 0 N
11 10 adantr N 0 I 0 I < N P : 0 N V I 0 N
12 1 11 ffvelrnd N 0 I 0 I < N P : 0 N V P I V