let N be with_zero set ; :: thesis: for S being non empty with_non-empty_values IC-Ins-separated Mem-Struct over N
for p being PartState of S
for k being Nat holds IC (DecIC (p,k)) = (IC p) -' k

let S be non empty with_non-empty_values IC-Ins-separated Mem-Struct over N; :: thesis: for p being PartState of S
for k being Nat holds IC (DecIC (p,k)) = (IC p) -' k

let p be PartState of S; :: thesis: for k being Nat holds IC (DecIC (p,k)) = (IC p) -' k
let k be Nat; :: thesis: IC (DecIC (p,k)) = (IC p) -' k
IC in dom (Start-At (((IC p) -' k),S)) by TARSKI:def 1;
hence IC (DecIC (p,k)) = (Start-At (((IC p) -' k),S)) . (IC ) by FUNCT_4:13
.= (IC p) -' k by FUNCOP_1:72 ;
:: thesis: verum