
theorem Th944:
Sum digits(276,10) = 15
proof
  thus Sum digits(276,10) = Sum <%6,7%>+Sum <%2%> by Th943,AFINSQ_2:55
  .= (6 + 7) + Sum <%2%> by AFINSQ_2:54
  .= 13 + 2 by AFINSQ_2:53
  .= 15;
end;
