#include <bits/stdc++.h>
using namespace std;
long long p = 1e9 + 7;
long long cs[1005][1005];
long long dp[1005][1005][2][2];
long long DP[1005];
int main() {
  long long n, k;
  cin >> n >> k;
  for (long long i = 0; i <= n; i++)
    for (long long j = 0; j <= i; j++)
      cs[i][j] = j ? (cs[i - 1][j] + cs[i - 1][j - 1]) % p : 1;
  dp[0][0][1][0] = 1;
  for (long long i = 1; i <= n; i++) {
    for (long long j = 0; j < i; j++)
      for (long long kk = 0; kk < 2; kk++)
        for (long long l = 0; l < 2; l++) {
          if (!kk)
            dp[i][j + 1][l][0] = (dp[i][j + 1][l][0] + dp[i - 1][j][kk][l]) % p;
          if (i < n)
            dp[i][j + 1][l][1] = (dp[i][j + 1][l][1] + dp[i - 1][j][kk][l]) % p;
          dp[i][j][l][0] = (dp[i][j][l][0] + dp[i - 1][j][kk][l]) % p;
        }
  }
  for (long long i = 0; i <= n; i++) {
    for (long long j = 0; j < 2; j++)
      for (long long k = 0; k < 2; k++) DP[i] = (DP[i] + dp[n][i][j][k]) % p;
    for (long long j = 2; j <= n - i; j++) DP[i] = (DP[i] * j) % p;
  }
  for (long long i = n - 1; i >= 0; i--)
    for (long long j = i + 1; j <= n; j++) {
      DP[i] = (DP[i] - (cs[j][i] * DP[j]) % p + p) % p;
    }
  cout << DP[k] << endl;
}
