T=[1,1,1,1,2]
P=[2,3,5,7,11,13]
def NP(N):
    global P
    if P[-1]<=N:
        for n in range(P[-1]+2,N+1,2):
            isP=True
            i=1
            while P[i]**2<=n:
                if n%P[i]==0:
                    isP=False
                    break
                i+=1
            if isP :
                P.append(n)
        return len(P)
    for i in range(len(P)):
        if P[i]>N:
            return i
            
def redJohn(n):
    global T
    for _ in range(n+1-len(T)):
        T.append(T[-1]+T[-4])
    return NP(T[n])