I'm confused from reading your question also, but. . . I think you are referring to the mathematical term "Summation" (which uses the Greek letter Sigma). Summation uses recursion which is illustrated in Bruce Eckel's Thinking in C++ tutorial as:
void removeHat(char cat) {
  for(char c = 'A'; c < cat; c++)
    cout << " ";
  if(cat <= 'Z') {
    cout << "cat " << cat << endl;
    removeHat(cat + 1); // Recursive call
  } else
    cout << "VOOM!!!" << endl;
}