findNextPrime.js

let primes = [ ]
const findNextPrime = (primeArray) => {
	let foundPrime = false
	for(np = 2; !foundPrime; np++) { 
		let isPrime = true 
		while(isPrime){
			for(p = 0; p < primeArray.length; p++) {
				if (np % primes[p] == 0) {
          isPrime = false
          break
				}
			}
			if (isPrime == 1) {
				foundPrime = 1
        return np
			}
		}
	}
}
let newPrime = findNextPrime(primes)
console.log('newPrime: ', newPrime);
primes.push(newPrime)
console.log(primes)