--- title: 10001st prime localeTitle: 10001st prime --- ## Problema 7: 10001st prime ### Método: * Un número primo es un número que se divide entre 1 y sí mismo. * Podemos encontrar que un número es primo si no es divisible por otros números primos más pequeños que él mismo. ### Solución: ```js function nthPrime(n) { //Primes array which will store all the prime numbers const primes = [2]; //Num is the number we want to check let num = 3, isPrime = true; //Looping until primes array is equal to n while (primes.length < n){ //All the primes numbers of a number is always <= it's square root let max = Math.ceil(Math.sqrt(num)); for (let i = 0; primes[i] <= max; i++){ if (num % primes[i] == 0) { //Looping till we find the prime isPrime = false; break; } } //if Prime found, push it to the array if (isPrime) primes.push(num); isPrime = true; //An optimization technique, since we know of all even numbers only 2 is a prime number, we can skip the rest num+=2; } //Returning the last number return primes[primes.length-1]; } ``` \- [Ejecutar código](https://repl.it/@ezioda004/Project-Euler-Problem-7-10001st-prime) ### Referencias: * [Wikipedia](https://en.wikipedia.org/wiki/Prime_number)