Metamath Proof Explorer


Theorem wwlknvtx

Description: The symbols of a word W representing a walk of a fixed length N are vertices. (Contributed by AV, 16-Mar-2022)

Ref Expression
Assertion wwlknvtx W N WWalksN G i 0 N W i Vtx G

Proof

Step Hyp Ref Expression
1 wwlknbp1 W N WWalksN G N 0 W Word Vtx G W = N + 1
2 simp2 N 0 W Word Vtx G W = N + 1 W Word Vtx G
3 nn0z N 0 N
4 fzval3 N 0 N = 0 ..^ N + 1
5 3 4 syl N 0 0 N = 0 ..^ N + 1
6 5 3ad2ant1 N 0 W Word Vtx G W = N + 1 0 N = 0 ..^ N + 1
7 6 eleq2d N 0 W Word Vtx G W = N + 1 i 0 N i 0 ..^ N + 1
8 7 biimpa N 0 W Word Vtx G W = N + 1 i 0 N i 0 ..^ N + 1
9 oveq2 W = N + 1 0 ..^ W = 0 ..^ N + 1
10 9 eleq2d W = N + 1 i 0 ..^ W i 0 ..^ N + 1
11 10 3ad2ant3 N 0 W Word Vtx G W = N + 1 i 0 ..^ W i 0 ..^ N + 1
12 11 adantr N 0 W Word Vtx G W = N + 1 i 0 N i 0 ..^ W i 0 ..^ N + 1
13 8 12 mpbird N 0 W Word Vtx G W = N + 1 i 0 N i 0 ..^ W
14 wrdsymbcl W Word Vtx G i 0 ..^ W W i Vtx G
15 2 13 14 syl2an2r N 0 W Word Vtx G W = N + 1 i 0 N W i Vtx G
16 15 ralrimiva N 0 W Word Vtx G W = N + 1 i 0 N W i Vtx G
17 1 16 syl W N WWalksN G i 0 N W i Vtx G