import sys
input=lambda: sys.stdin.readline().rstrip()
n=int(input())
mod=10**9+7
D=[[0]*3 for _ in range(n)]
D[1][0]=1
D[1][1]=1
D[1][2]=0
for i in range(2,n):
  D[i][0]=D[i-1][2]
  D[i][1]=(D[i-1][0]+D[i-1][2])%mod
  D[i][2]=D[i-1][1]
print(sum(D[-1])%mod)