| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mdegxrcl.d |  |-  D = ( I mDeg R ) | 
						
							| 2 |  | mdegxrcl.p |  |-  P = ( I mPoly R ) | 
						
							| 3 |  | mdegxrcl.b |  |-  B = ( Base ` P ) | 
						
							| 4 |  | eqid |  |-  ( 0g ` R ) = ( 0g ` R ) | 
						
							| 5 |  | eqid |  |-  { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } = { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } | 
						
							| 6 |  | eqid |  |-  ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) = ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) | 
						
							| 7 | 1 2 3 4 5 6 | mdegval |  |-  ( F e. B -> ( D ` F ) = sup ( ( ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) " ( F supp ( 0g ` R ) ) ) , RR* , < ) ) | 
						
							| 8 |  | imassrn |  |-  ( ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) " ( F supp ( 0g ` R ) ) ) C_ ran ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) | 
						
							| 9 | 5 6 | tdeglem1 |  |-  ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) : { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } --> NN0 | 
						
							| 10 |  | frn |  |-  ( ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) : { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } --> NN0 -> ran ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) C_ NN0 ) | 
						
							| 11 | 9 10 | mp1i |  |-  ( F e. B -> ran ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) C_ NN0 ) | 
						
							| 12 |  | nn0ssre |  |-  NN0 C_ RR | 
						
							| 13 |  | ressxr |  |-  RR C_ RR* | 
						
							| 14 | 12 13 | sstri |  |-  NN0 C_ RR* | 
						
							| 15 | 11 14 | sstrdi |  |-  ( F e. B -> ran ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) C_ RR* ) | 
						
							| 16 | 8 15 | sstrid |  |-  ( F e. B -> ( ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) " ( F supp ( 0g ` R ) ) ) C_ RR* ) | 
						
							| 17 |  | supxrcl |  |-  ( ( ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) " ( F supp ( 0g ` R ) ) ) C_ RR* -> sup ( ( ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) " ( F supp ( 0g ` R ) ) ) , RR* , < ) e. RR* ) | 
						
							| 18 | 16 17 | syl |  |-  ( F e. B -> sup ( ( ( y e. { x e. ( NN0 ^m I ) | ( `' x " NN ) e. Fin } |-> ( CCfld gsum y ) ) " ( F supp ( 0g ` R ) ) ) , RR* , < ) e. RR* ) | 
						
							| 19 | 7 18 | eqeltrd |  |-  ( F e. B -> ( D ` F ) e. RR* ) |