N=int(input()) k = [0 for x in range(100003)] kk = [0 for x in range(100003)] p = [0 for x in range(100003)] k[0:3] = [1,0,1] kk[0:3] = [0,1,0] p[0:3] = [0,1,1] for i in range(1,N): p[i]=(k[i-1]+kk[i-1])%(10**9+7) k[i+1]=p[i]%(10**9+7) kk[i+2]=p[i]%(10**9+7) print((k[N-1]+kk[N-1]+p[N-1])%(10**9+7))