
theorem Th1078:
Sum digits(125,10) = 8
proof
  thus Sum digits(125,10) = Sum <%5,2%>+Sum <%1%> by Th1077,AFINSQ_2:55
  .= (5 + 2) + Sum <%1%> by AFINSQ_2:54
  .= 7 + 1 by AFINSQ_2:53
  .= 8;
end;
