import java.io.*
import java.util.*
import java.lang.*
import java.lang.Math.*


fun solve() {
    val S = rd.readLong()

    val ans = (1L .. S/3L)
            .map{ nHkMod(it, max(S-3*it, 0L))}
            .fold(0L){x,y -> (x+y)%MOD}
    println(ans)
}


//val rd = debug.Reader("abc", "178", "d", "sample-1")
val rd = Reader()


fun powMod(X: Long, N: Long, Mod: Long = 1_000_000_007L): Long {
    return when (N) {
        0L -> 1L
        else -> {
            when (N%2) {
                1L -> powMod((X * X) % Mod, N / 2, Mod) * X % Mod
                else -> powMod((X * X) % Mod, N / 2, Mod)
            }
        }
    }
}

fun invMod(X: Long, Mod: Long = 1_000_000_007L): Long {
    return powMod(X, Mod-2, Mod)
}

fun permMod(N: Long, K: Long, Mod: Long = 1_000_000_007L): Long {
    return (N downTo N-K+1).fold(1L){ x,y -> x*y%Mod }
}

fun nCkMod(N: Long, K: Long, Mod: Long = 1_000_000_007L): Long {
    return permMod(N,K) *  invMod(permMod(K,K)) % Mod
}

fun nHkMod(N: Long, K: Long, Mod: Long = 1_000_000_007L): Long {
    return nCkMod(N+K-1, K, Mod)
}


fun main(args: Array<String>) {
    try {
        var exception: Throwable? = null
        val sth = Thread(null, SolveThread(), "solveThread", 128 * 1024 * 1024)
        sth.setUncaughtExceptionHandler { _, e -> exception = e }
        sth.start(); sth.join()
        if (exception != null) throw exception!! }
    catch (e: Exception) { throw e }
    finally { rd.close() }
}
const val MOD = 1_000_000_007L; const val INF = Int.MAX_VALUE/2; const val LINF = Long.MAX_VALUE/2
const val EPS = 1e-9; fun DBLEQ(a: Double, b: Double): Boolean {return abs(a - b) < EPS}
data class IntPair(val first: Int, val second: Int); data class LongPair(val first: Long, val second: Long)
data class To(val idx: Int, val cost: Long)
fun <T>edge(V: Int): Array<ArrayList<T>> { return Array(V){ArrayList<T>()} }
val errPrintln: (Any) -> Unit = { msg -> System.err.println(msg) }
fun rAssert(exp: Boolean, lazyMsg: () -> String = {""}) {
    if (!exp) { val msg = lazyMsg(); errPrintln("EAssert Error: $msg"); throw Error(msg) }
}
fun tAssert(exp: Boolean, lazyMsg: () -> String = {""}) {
    if (!exp) { val msg = lazyMsg(); errPrintln("TAssert Error: $msg"); Thread.sleep(3000) }
}
class SolveThread : Runnable {
    override fun run() { solve() }
}
class Reader {
    private val br = BufferedReader(InputStreamReader(System.`in`))
    val readString: () -> String = { br.readLine() }
    val readInt: () -> Int = { br.readLine().toInt() }
    val readLong: () -> Long = { br.readLine().toLong() }
    val readDouble: () -> Double = { br.readLine().toDouble() }
    val readListInt: () -> List<Int> = { br.readLine().split(' ').map { it.toInt() } }
    val readListLong: () -> List<Long> = { br.readLine().split(' ').map { it.toLong() } }
    val readIntArray: () -> IntArray = { readListInt().toIntArray() }
    val readLongArray: () -> LongArray = { readListLong().toLongArray() }
    val readListStringCol: (Int) -> List<String> = { N -> (0 until N).map { readString() } }
    val readListIntCol: (Int) -> List<Int> = { N -> (0 until N).map { readInt() } }
    val readListIntCols: (Int) -> List<List<Int>> = { N -> (0 until N).map { readListInt() } }
    val readListLongCol: (Int) -> List<Long> = { N -> (0 until N).map { readLong() } }
    val readListLongCols: (Int) -> List<List<Long>> = { N -> (0 until N).map { readListLong() } }
    val close: () -> Unit = { br.close() }
    protected fun finalize() { close() }
}


Measured memory_bytes: 36408