theorem Th8:
  x in { 9,10,11,12,13 } implies [x,{},<*d4,d5,k5,k6*>] in
  SCMPDS-Instr
proof
  assume
A1: x in { 9,10,11,12,13 };
  then x = 9 or x=10 or x=11 or x=12 or x=13 by ENUMSET1:def 3;
  then reconsider x as Element of Segm 15 by NAT_1:44;
  k5 is Element of INT & k6 is Element of INT by INT_1:def 2;
  then [x,{},<*d4,d5,k5,k6*>] in S5 by A1;
  hence thesis by XBOOLE_0:def 3;
end;
