{-# LANGUAGE BangPatterns #-}

import Control.Applicative
import Control.Monad
import Data.List
import Debug.Trace (traceShow)
import qualified Data.ByteString.Char8 as B

import Data.Array

inf :: Int
inf = 10 ^ 9 + 7

solve :: Int -> Int
solve n = (memo ! (n, 0) + memo ! (n, 1) + memo ! (n, 2)) `mod` inf
  where
    memo :: Array (Int, Int) Int
    memo = listArray ((1, 0), (n, 2)) [go i j | i <- [1 .. n], j <- [0 .. 2]]

    go 1 0 = 0
    go 1 1 = 1
    go 1 2 = 0
    go i 0 = memo ! (i - 1, 1) `mod` inf + memo ! (i - 1, 2) `mod` inf
    go i 1 = memo ! (i - 1, 0)
    go i 2 = memo ! (i - 1, 1)

main :: IO ()
main = do
    n <- readLn
    print $ solve n