Metamath Proof Explorer


Theorem stgredg

Description: The edges of the star graph S_N. (Contributed by AV, 11-Sep-2025)

Ref Expression
Assertion stgredg ( 𝑁 ∈ ℕ0 → ( Edg ‘ ( StarGr ‘ 𝑁 ) ) = { 𝑒 ∈ 𝒫 ( 0 ... 𝑁 ) ∣ ∃ 𝑥 ∈ ( 1 ... 𝑁 ) 𝑒 = { 0 , 𝑥 } } )

Proof

Step Hyp Ref Expression
1 edgval ( Edg ‘ ( StarGr ‘ 𝑁 ) ) = ran ( iEdg ‘ ( StarGr ‘ 𝑁 ) )
2 stgriedg ( 𝑁 ∈ ℕ0 → ( iEdg ‘ ( StarGr ‘ 𝑁 ) ) = ( I ↾ { 𝑒 ∈ 𝒫 ( 0 ... 𝑁 ) ∣ ∃ 𝑥 ∈ ( 1 ... 𝑁 ) 𝑒 = { 0 , 𝑥 } } ) )
3 2 rneqd ( 𝑁 ∈ ℕ0 → ran ( iEdg ‘ ( StarGr ‘ 𝑁 ) ) = ran ( I ↾ { 𝑒 ∈ 𝒫 ( 0 ... 𝑁 ) ∣ ∃ 𝑥 ∈ ( 1 ... 𝑁 ) 𝑒 = { 0 , 𝑥 } } ) )
4 rnresi ran ( I ↾ { 𝑒 ∈ 𝒫 ( 0 ... 𝑁 ) ∣ ∃ 𝑥 ∈ ( 1 ... 𝑁 ) 𝑒 = { 0 , 𝑥 } } ) = { 𝑒 ∈ 𝒫 ( 0 ... 𝑁 ) ∣ ∃ 𝑥 ∈ ( 1 ... 𝑁 ) 𝑒 = { 0 , 𝑥 } }
5 3 4 eqtrdi ( 𝑁 ∈ ℕ0 → ran ( iEdg ‘ ( StarGr ‘ 𝑁 ) ) = { 𝑒 ∈ 𝒫 ( 0 ... 𝑁 ) ∣ ∃ 𝑥 ∈ ( 1 ... 𝑁 ) 𝑒 = { 0 , 𝑥 } } )
6 1 5 eqtrid ( 𝑁 ∈ ℕ0 → ( Edg ‘ ( StarGr ‘ 𝑁 ) ) = { 𝑒 ∈ 𝒫 ( 0 ... 𝑁 ) ∣ ∃ 𝑥 ∈ ( 1 ... 𝑁 ) 𝑒 = { 0 , 𝑥 } } )