Start Number:
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Number: 2 is prime
Rec: 2
Rem: 0
Com:2
Copy of the last prime
as new counter
Explanation:
Rec - is the last row of the respective rectangle with the width of a prime
Rem - is the remainder by trying to build a rectangle (if no remainder, the number is no prime)
Com - is the "completer" for better orientation (rem - rec = com)
NoPr! - Marks, why the number is no prime