
theorem Th195:
Sum digits(256,10) = 13
proof
  thus Sum digits(256,10) = Sum <%6,5%>+Sum <%2%> by Th194,AFINSQ_2:55
  .= (6 + 5) + Sum <%2%> by AFINSQ_2:54
  .= 11 + 2 by AFINSQ_2:53
  .= 13;
end;
