let m, k be Nat; :: thesis: for r being Tuple of (m + 2),(k -SD ) st m >= 1 & k >= 2 holds
(SDDec (M0 r)) + (SDDec (DecSD 0 ,(m + 2),k)) = (SDDec (Mmin r)) + (SDDec (SDMax (m + 2),m,k))
let r be Tuple of (m + 2),(k -SD ); :: thesis: ( m >= 1 & k >= 2 implies (SDDec (M0 r)) + (SDDec (DecSD 0 ,(m + 2),k)) = (SDDec (Mmin r)) + (SDDec (SDMax (m + 2),m,k)) )
assume A1:
( m >= 1 & k >= 2 )
; :: thesis: (SDDec (M0 r)) + (SDDec (DecSD 0 ,(m + 2),k)) = (SDDec (Mmin r)) + (SDDec (SDMax (m + 2),m,k))
then A2:
m + 2 > 1
by Lm1;
A3:
m in Seg (m + 2)
by A1, FINSEQ_3:10;
(SDDec (M0 r)) + (SDDec (SDMin (m + 2),m,k)) =
(SDDec (Mmin r)) + (SDDec (DecSD 0 ,(m + 2),k))
by A1, Th11
.=
(SDDec (Mmin r)) + 0
by A2, RADIX_5:6
;
then (SDDec (Mmin r)) + (SDDec (SDMax (m + 2),m,k)) =
(SDDec (M0 r)) + ((SDDec (SDMax (m + 2),m,k)) + (SDDec (SDMin (m + 2),m,k)))
.=
(SDDec (M0 r)) + (SDDec (DecSD 0 ,(m + 2),k))
by A1, A2, A3, RADIX_5:17
;
hence
(SDDec (M0 r)) + (SDDec (DecSD 0 ,(m + 2),k)) = (SDDec (Mmin r)) + (SDDec (SDMax (m + 2),m,k))
; :: thesis: verum