
theorem Th1276:
Sum digits(3650,10) = 14
proof
  thus Sum digits(3650,10) = Sum <%0,5,6%>+Sum <%3%> by Th1275,AFINSQ_2:55
  .= Sum <%0,5%> + Sum <%6%> + Sum <%3%> by AFINSQ_2:55
  .= (0 + 5) + Sum <%6%> + Sum <%3%> by AFINSQ_2:54
  .= (0 + 5 + 6) + Sum <%3%> by AFINSQ_2:53
  .= 11 + 3 by AFINSQ_2:53
  .= 14;
end;
