
theorem
  for X be set for x be Subset of X for q be FinSequence of BOOLEAN
  holds len MergeSequence(<*x*>,q) = 1
proof
  let X be set;
  let x be Subset of X;
  let q be FinSequence of BOOLEAN;
  thus len MergeSequence(<*x*>,q) = len <*x*> by Def1
    .= 1 by FINSEQ_1:39;
end;
