#include <bits/stdc++.h>
using namespace std;

const int MAX_N	= 1000000;
const int iMod	= 1000000007;

long long Step1[ MAX_N + 5 ];
long long Step2[ MAX_N + 5 ];
long long Step3[ MAX_N + 5 ];

int main( int argc, char *argv[] )
{
int i;
int N;
long long iAns;

	ios::sync_with_stdio( false );
	cin.tie( 0 );

	cin >> N;
	Step1[ 1 ] = 1;
	Step2[ 2 ] = 1;
	Step3[ 3 ] = 1;
	for( i = 1; i < N; i++ )
	{
		Step1[ i + 1 ] += Step2[ i ];
		Step1[ i + 1 ] += Step3[ i ];
		Step2[ i + 2 ] += Step1[ i ];
		Step2[ i + 2 ] += Step3[ i ];
		Step3[ i + 3 ] += Step1[ i ];
		Step3[ i + 3 ] += Step2[ i ];
		Step1[ i + 1 ] %= iMod;
		Step2[ i + 2 ] %= iMod;
		Step3[ i + 3 ] %= iMod;
	}

	iAns = Step1[ N ] + Step2[ N ] + Step3[ N ];
	iAns %= iMod;
	cout << iAns << endl;

	return 0;
}