reserve a,a1,a2,v,v1,v2,x for object;
reserve V,A for set;
reserve m,n for Nat;
reserve S,S1,S2 for FinSequence;
reserve D,D1,D2 for NonatomicND of V,A;

theorem
  for V being non empty set
  for v being Element of V holds
  naming(V,A,<*v*>,a) = naming(V,A,v,a)
  proof
    let V be non empty set;
    let v be Element of V;
    set f = <*v*>;
A1: len f = 1 & f.1 = v by FINSEQ_1:40;
    len(namingSeq(V,A,f,a)) = len f by Def14;
    hence thesis by A1,Def14;
  end;
