Create a boolean array " prime [ 0 . . n ] " and initialize all entries it as true . A value in prime [ i ] will finally be false if i is Not a prime , else true .
var prime = Array . from ( { length : parseInt ( ( MAX + 1.0 ) ) } , ( _ , i ) => false ) ; function SieveOfEratosthenes ( ) { for ( i = 0 ; i <= MAX ; i ++ ) prime [ i ] = true ; prime [ 1 ] = false ; for ( p = 2 ; p * p <= MAX ; p ++ ) {