
theorem Th326:
Sum digits(570,10) = 12
proof
  thus Sum digits(570,10) = Sum <%0,7%>+Sum <%5%> by Th325,AFINSQ_2:55
  .= (0 + 7) + Sum <%5%> by AFINSQ_2:54
  .= 7 + 5 by AFINSQ_2:53
  .= 12;
end;
