
theorem Th757:
Sum digits(330,10) = 6
proof
  thus Sum digits(330,10) = Sum <%0,3%>+Sum <%3%> by Th756,AFINSQ_2:55
  .= (0 + 3) + Sum <%3%> by AFINSQ_2:54
  .= 3 + 3 by AFINSQ_2:53
  .= 6;
end;
