| Step |
Hyp |
Ref |
Expression |
| 1 |
|
stgrvtx0.g |
⊢ 𝐺 = ( StarGr ‘ 𝑁 ) |
| 2 |
|
stgrvtx0.v |
⊢ 𝑉 = ( Vtx ‘ 𝐺 ) |
| 3 |
1 2
|
stgrvtx0 |
⊢ ( 𝑁 ∈ ℕ0 → 0 ∈ 𝑉 ) |
| 4 |
2
|
dfclnbgr4 |
⊢ ( 0 ∈ 𝑉 → ( 𝐺 ClNeighbVtx 0 ) = ( { 0 } ∪ ( 𝐺 NeighbVtx 0 ) ) ) |
| 5 |
3 4
|
syl |
⊢ ( 𝑁 ∈ ℕ0 → ( 𝐺 ClNeighbVtx 0 ) = ( { 0 } ∪ ( 𝐺 NeighbVtx 0 ) ) ) |
| 6 |
1 2
|
stgrnbgr0 |
⊢ ( 𝑁 ∈ ℕ0 → ( 𝐺 NeighbVtx 0 ) = ( 𝑉 ∖ { 0 } ) ) |
| 7 |
6
|
uneq2d |
⊢ ( 𝑁 ∈ ℕ0 → ( { 0 } ∪ ( 𝐺 NeighbVtx 0 ) ) = ( { 0 } ∪ ( 𝑉 ∖ { 0 } ) ) ) |
| 8 |
3
|
snssd |
⊢ ( 𝑁 ∈ ℕ0 → { 0 } ⊆ 𝑉 ) |
| 9 |
|
undif |
⊢ ( { 0 } ⊆ 𝑉 ↔ ( { 0 } ∪ ( 𝑉 ∖ { 0 } ) ) = 𝑉 ) |
| 10 |
8 9
|
sylib |
⊢ ( 𝑁 ∈ ℕ0 → ( { 0 } ∪ ( 𝑉 ∖ { 0 } ) ) = 𝑉 ) |
| 11 |
5 7 10
|
3eqtrd |
⊢ ( 𝑁 ∈ ℕ0 → ( 𝐺 ClNeighbVtx 0 ) = 𝑉 ) |