
theorem Th465:
Sum digits(1360,10) = 10
proof
  thus Sum digits(1360,10) = Sum <%0,6,3%>+Sum <%1%> by Th464,AFINSQ_2:55
  .= Sum <%0,6%> + Sum <%3%> + Sum <%1%> by AFINSQ_2:55
  .= (0 + 6) + Sum <%3%> + Sum <%1%> by AFINSQ_2:54
  .= (0 + 6 + 3) + Sum <%1%> by AFINSQ_2:53
  .= 9 + 1 by AFINSQ_2:53
  .= 10;
end;
