may=[2,3,5,7,13,17,19,31,61,89,107,127,521,607,1279,2203,2281,3217,4253,4423,9689,9941,11213,19937,21701,23209,44497,86243,110503,132049,216091,756839,859433,1257787,1398269]

while True:
    try:
        n=int(input())
        if 2**n-1 in may:
            print("yes")
        elif n==0:
            break
        else:
            print("no")
    except:
        break

        if 2**n-1 in may:

if n in may:

        if 2**n-1 in may:

if n in may:

AC了，謝謝