
theorem Th306:
Sum digits(380,10) = 11
proof
  thus Sum digits(380,10) = Sum <%0,8%>+Sum <%3%> by Th305,AFINSQ_2:55
  .= (0 + 8) + Sum <%3%> by AFINSQ_2:54
  .= 8 + 3 by AFINSQ_2:53
  .= 11;
end;
