reserve i1 for Element of INT;
reserve j1,j2,j3 for Integer;
reserve p,s,k,n for Nat;
reserve x,y,xp,yp for set;
reserve G for Group;
reserve a,b for Element of G;
reserve F for FinSequence of G;
reserve I for FinSequence of INT;

theorem
  for i1 st i1 = 0 holds i1 is_a_unity_wrt addint by BINOP_2:4,SETWISEO:14;
