//Counts the number of primes under 25
function primesUnder25(){
	// Candidates will start out by holding the numbers from 1 to 25
	var candidates = [];
    var i;
	do{
		// Add to the list and then increment
		candidates += i;
		i++;
	} while(i < 25) // Stop once we get to 25
 
    // We have to remove all compostes, and remove 1.
	// Every composite under 25 is divisible by 2 or 3
	// First we will generate and remove all multiples of 2 and 3
	var composites = []
	for(var prime of [2,3]){
		for(var i=1; (prime ** i) <= 25; i++){ // Multiply each prime by each i to generate all multiples of that prime
			composites.push(prime ** i)
		}	
	}
	// For each composite number, we will remove the candidate at that index
    composites = composites.sort().reverse(); // (Do this from biggest to smallest or else the array indices shift after you delete each one)
	composites.forEach(ind => {
		candidates=candidates.slice(0, ind)+candidates.slice(ind+1) // Remove at (ind)th index
	})
 
	// Lastly, don't forget to remove 1 because that's not prime
	candidates = candidates.slice(1)
	return candidates;
}
 
console.log(primesUnder25()) // Huh, that's weird... seems to work though, so good enough for me.

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