
theorem Th344:
Sum digits(741,10) = 12
proof
  thus Sum digits(741,10) = Sum <%1,4%>+Sum <%7%> by Th343,AFINSQ_2:55
  .= (1 + 4) + Sum <%7%> by AFINSQ_2:54
  .= 5 + 7 by AFINSQ_2:53
  .= 12;
end;
