#!/usr/bin/env python3

def primes(n):
    sieve = [True] * n
    for p in range(2, int(n**0.5)):
        if not sieve[p]:
            continue
        for i in range(p**2, n, p):
            sieve[i] = False
    return [False, False] + sieve[2:]

def is_prime(p):
    if p >= len(sieve):
        raise LimitError
    return sieve[p]

def getnum(n, c):
    m = n//6
    if c:
        return 3*(m-1)*m + 2
    return 3*m*(m+1) + 1

sieve = primes(10**6)
target = 2000

c = 2
n = 6

while c < target:
    n += 6
    if not is_prime(n-1):
        continue
    c += is_prime(n+1) and is_prime(2*n + 5)
    if c == target:
        flag = True
        break
    c += is_prime(n+5) and is_prime(2*n-7)
else:
    flag = False

print(getnum(n, flag))