reserve s for set,
  i,j for natural Number,
  k for Nat,
  x,x1,x2,x3 for Real,
  r,r1,r2,r3,r4 for Real,
  F,F1,F2,F3 for real-valued FinSequence,
  R,R1,R2 for Element of i-tuples_on REAL;

theorem
  Product (i|->1) = 1
proof
  i is Nat by TARSKI:1;
  then Product (i |-> the_unity_wrt multreal) = the_unity_wrt multreal
  by SETWOP_2:25;
  hence thesis by BINOP_2:7;
end;
