Issue 4164 - sieve Sample D Program -- need documentation for array …

…representation

overview.dd

@@ -1074,6 +1074,16 @@ int main()
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+$(P NB: The expectation may that array index x represents the number x.  But it is not so.
+
+At first glance the i + i + 3 seems very odd indeed.
+
+However, if one were to consider each index, it would mean that the first element would represent 0 + 0 + 3 = 3;
+the second element would represent 1 + 1 + 3 = 5;
+the third element would represent 2 + 2 + 3 = 7;
+and so on and so forth.
+
+So the numbers represented by the array actually go from 3 to (8190 + 8190 + 3), or 16383.
 )
 
 Macros: