
theorem Th732:
Sum digits(63,10) = 9
proof
  thus Sum digits(63,10) = Sum <%3%>+Sum <%6%> by Th731,AFINSQ_2:55
  .= 3 + Sum <%6%> by AFINSQ_2:53
  .= 3+6 by AFINSQ_2:53
  .= 9;
end;
