PrimeTriangle

package com.company.one;

import java.util.Arrays;
import java.util.Scanner;

public class PrimeTriangle {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int n = scanner.nextInt();

        boolean[] primes = new boolean[n + 1];

        Arrays.fill(primes, true); // set all values in `primes` to true
        for (int number = 0; number < primes.length ; number++) {
            int sqrt = (int) Math.sqrt(number) + 1 ;
            for (int sq = 2; sq < sqrt; sq++) {
                if (number % sq == 0) {
                    primes[number] = false;
                    break;
                }
            }
        }

        for (int i = 1; i <= n; i++) {
            if (!primes[i]) {
                continue;
            }

            for (int j = 1; j <= i; j++) {
                if (primes[j]) {
                    System.out.print(1);
                } else {
                    System.out.print(0);
                }
            }
            System.out.println();
        }
    }
}