Metamath Proof Explorer


Theorem slwpss

Description: A proper superset of a Sylow subgroup is not a P -group. (Contributed by Mario Carneiro, 16-Jan-2015)

Ref Expression
Hypothesis slwispgp.1
|- S = ( G |`s K )
Assertion slwpss
|- ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> -. P pGrp S )

Proof

Step Hyp Ref Expression
1 slwispgp.1
 |-  S = ( G |`s K )
2 simp3
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> H C. K )
3 2 pssned
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> H =/= K )
4 2 pssssd
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> H C_ K )
5 4 biantrurd
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> ( P pGrp S <-> ( H C_ K /\ P pGrp S ) ) )
6 1 slwispgp
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) ) -> ( ( H C_ K /\ P pGrp S ) <-> H = K ) )
7 6 3adant3
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> ( ( H C_ K /\ P pGrp S ) <-> H = K ) )
8 5 7 bitrd
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> ( P pGrp S <-> H = K ) )
9 8 necon3bbid
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> ( -. P pGrp S <-> H =/= K ) )
10 3 9 mpbird
 |-  ( ( H e. ( P pSyl G ) /\ K e. ( SubGrp ` G ) /\ H C. K ) -> -. P pGrp S )