reserve k,n for Nat,
  x,y,z,y1,y2 for object,X,Y for set,
  f,g for Function;
reserve p,q,r,s,t for XFinSequence;
reserve D for set;

theorem Th32:
  (<%x%>^p).0 = x
proof
  0 in 1 by CARD_1:49,TARSKI:def 1;
  then 0 in dom <%x%> by Def4;
  then (<%x%>^p).0 = <%x%>.0 by Def3;
  hence thesis;
end;
