__  __ __            _        ___           
 / / / // /___ _ __ _ ( )___   / _ \ ___  _  __ ___  ___  ___ _ ___ 
/ /_/ // // _ `//  ' \|/(_-<  / , _// -_)| |/ // -_)/ _ \/ _ `// -_)
\____//_/ \_,_//_/_/_/ /___/ /_/|_| \__/ |___/ \__//_//_/\_, / \__/ 
                             Prime Spiral Generator     /___/
 

    


Numbers:         
Start from :     
Dots per number:   
    Black:  numer zero or one
    White:  prime number
    Red:    odd unique factors    
    Blue:   even unique factors   
    Green:  no unique factors   
 Color dot:  distinct prime factors
 Black dot:  n^2 + n + 41 (Euler's)

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by Alexandre Gomes Gaigalas, code derived from Miroslav Magda's Javascript implementation of the Ulam Spiral.