
theorem Th365:
Sum digits(260,10) = 8
proof
  thus Sum digits(260,10) = Sum <%0,6%>+Sum <%2%> by Th364,AFINSQ_2:55
  .= (0 + 6) + Sum <%2%> by AFINSQ_2:54
  .= 6 + 2 by AFINSQ_2:53
  .= 8;
end;
