#include <bits/stdc++.h>
#define AOTSUKI

using namespace std;
constexpr bool isMultiCase = 0;

// #include "angel/math/modint.hpp"

using ll = long long;
template <class T> constexpr int len(const T &c) {
    return int(std::ssize(c));
}
template <class T> using V = vector<T>;
template <class T> using RevPq = priority_queue<T, vector<T>, greater<T>>;
constexpr char eoln = '\n';
#define L(i, l, r) for (int i = (l); i < (r); ++i)
#define R(i, l, r) for (int i = (r) - 1; i >= (l); --i)
#define ALL(x) (x).begin(), (x).end()
#define fi first
#define se second

constexpr ll mod = 1000000007;

void solve() {
    int n, m; cin >> n >> m;

    vector dp(m + 1, vector(m + 1, 0ll));
    dp[m][0] = 1;
    L(t, 0, n) {
        vector ndp(m + 1, vector(m + 1, 0ll));
        L(i, 0, m + 1) {
            L(j, 0, m + 1) {
                // case 1 : choose 1

                // case 1-1 : choose (1, 0)
                if (i != 0 and j != m) {
                    ndp[i - 1][j + 1] += dp[i][j] * i;
                    ndp[i - 1][j + 1] %= mod;
                }

                // case 1-2 : choose (0, 1)
                if (j != 0) {
                    ndp[i][j - 1] += dp[i][j] * j;
                    ndp[i][j - 1] %= mod;
                }

                // case 2 : choose 2
                
                // case 2-1 : choose (2, 0)
                if (i >= 2 and j <= m - 2) {
                    ndp[i - 2][j + 2] += dp[i][j] * i * (i - 1) / 2;
                    ndp[i - 2][j + 2] %= mod;
                }
                // case 2-2 : choose (1, 1)
                if (i != 0) {
                    ndp[i - 1][j] += dp[i][j] * i * j;
                    ndp[i - 1][j] %= mod;
                }
                // case 2-3 : choose (2, 0)
                if (j >= 2) {
                    ndp[i][j - 2] += dp[i][j] * j * (j - 1) / 2;
                    ndp[i][j - 2] %= mod;
                }
            }
        }

        /*
        L(i, 0, m + 1) {
            L(j, 0, m + 1) {
                cerr << ndp[i][j] << ' ';
            }
            cerr << endl;
        }
        cerr << endl;
        */
        dp = move(ndp);
    }

    ll ans = 0;
    L(i, 0, m + 1) ans += dp[0][i];
    ans %= mod;
    cout << ans << endl;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    if (not isMultiCase) {
        solve();
    } else {
        int t;
        cin >> t;
        while (t--) solve();
    }
}