let R be Ring; :: thesis: for i1, il being Element of NAT holds NIC ((goto (i1,R)),il) = {i1}
let i1, il be Element of NAT ; :: thesis: NIC ((goto (i1,R)),il) = {i1}
now :: thesis: for x being set holds
( x in {i1} iff x in { (IC (Exec ((goto (i1,R)),s))) where s is Element of product (the_Values_of (SCM R)) : IC s = il } )
let x be set ; :: thesis: ( x in {i1} iff x in { (IC (Exec ((goto (i1,R)),s))) where s is Element of product (the_Values_of (SCM R)) : IC s = il } )
A1: now :: thesis: ( x = i1 implies x in { (IC (Exec ((goto (i1,R)),s))) where s is Element of product (the_Values_of (SCM R)) : IC s = il } )
reconsider il1 = il as Element of Values (IC ) by MEMSTR_0:def 6;
set I = goto (i1,R);
set t = the State of (SCM R);
set Q = the Instruction-Sequence of (SCM R);
assume A2: x = i1 ; :: thesis: x in { (IC (Exec ((goto (i1,R)),s))) where s is Element of product (the_Values_of (SCM R)) : IC s = il }
reconsider u = the State of (SCM R) +* ((IC ),il1) as Element of product (the_Values_of (SCM R)) by CARD_3:107;
reconsider P = the Instruction-Sequence of (SCM R) +* (il,(goto (i1,R))) as Instruction-Sequence of (SCM R) ;
A3: P /. il = P . il by PBOOLE:143;
IC in dom the State of (SCM R) by MEMSTR_0:2;
then A4: IC u = il by FUNCT_7:31;
il in NAT ;
then il in dom the Instruction-Sequence of (SCM R) by PARTFUN1:def 2;
then A5: P . il = goto (i1,R) by FUNCT_7:31;
then IC (Following (P,u)) = i1 by A4, A3, SCMRING2:15;
hence x in { (IC (Exec ((goto (i1,R)),s))) where s is Element of product (the_Values_of (SCM R)) : IC s = il } by A2, A3, A4, A5; :: thesis: verum
end;
now :: thesis: ( x in { (IC (Exec ((goto (i1,R)),s))) where s is Element of product (the_Values_of (SCM R)) : IC s = il } implies x = i1 )
assume x in { (IC (Exec ((goto (i1,R)),s))) where s is Element of product (the_Values_of (SCM R)) : IC s = il } ; :: thesis: x = i1
then ex s being Element of product (the_Values_of (SCM R)) st
( x = IC (Exec ((goto (i1,R)),s)) & IC s = il ) ;
hence x = i1 by SCMRING2:15; :: thesis: verum
end;
hence ( x in {i1} iff x in { (IC (Exec ((goto (i1,R)),s))) where s is Element of product (the_Values_of (SCM R)) : IC s = il } ) by A1, TARSKI:def 1; :: thesis: verum
end;
hence NIC ((goto (i1,R)),il) = {i1} by TARSKI:1; :: thesis: verum