# your code goes here
N=int(input())
M=10
for i in range(8):
    M*=10
M+=7
K1=[1]
K2=[0]
P=[0]
for i in range(1,N):
    K1.append(P[i-1])
    K2.append(K1[i-1])
    P.append(K1[i-1]+K2[i-1])
    P[i]%=M
 #   print(P)
A=K1[N-1]+K2[N-1]+P[N-1]
A%=M
print(A)