Description: The span of the singleton of a vector is an atom. (Contributed by NM, 18-Dec-2004) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | spansna | |- ( ( A e. ~H /\ A =/= 0h ) -> ( span ` { A } ) e. HAtoms ) | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | spansn |  |-  ( A e. ~H -> ( span ` { A } ) = ( _|_ ` ( _|_ ` { A } ) ) ) | 
						|
| 2 | 1 | adantr |  |-  ( ( A e. ~H /\ A =/= 0h ) -> ( span ` { A } ) = ( _|_ ` ( _|_ ` { A } ) ) ) | 
						
| 3 | h1da |  |-  ( ( A e. ~H /\ A =/= 0h ) -> ( _|_ ` ( _|_ ` { A } ) ) e. HAtoms ) | 
						|
| 4 | 2 3 | eqeltrd |  |-  ( ( A e. ~H /\ A =/= 0h ) -> ( span ` { A } ) e. HAtoms ) |