def check(x):
    if x==1 or x==0:
        return "NO"
    else:
        for i in range(2,int(x**0.5)+1):
            if x%i==0:
                return "NO"
        return "YES"
def huiwen(x):
    a=str(x)
    for i in range(len(a)//2):
        if a[::-1]==a:
            return 1
n=int(input())
for i in range(11,n+1):
    if check(i)=="YES"and huiwen(i)==1:
        print(i)