
theorem Th82:
Sum digits(165,10) = 12
proof
  thus Sum digits(165,10) = Sum <%5,6%>+Sum <%1%> by Th81,AFINSQ_2:55
  .= (5 + 6) + Sum <%1%> by AFINSQ_2:54
  .= 11 + 1 by AFINSQ_2:53
  .= 12;
end;
