#include <bits/stdc++.h>

using namespace std;

const int maxN = 1e3 + 9;
const int maxM = 1e3 + 9;
const int MOD = 1e9 + 7;

long long memo[maxN][maxM], N, M;
long long nCr[maxN][maxN];

long long dp (int row, int lastRowOnes) {
    if (row == N + 1)
        return 1;

    if (memo[row][lastRowOnes] != -1)
        return memo[row][lastRowOnes];

    long long res = 0;

    for (int powerOf2 = 2; powerOf2 <= 2 * M; powerOf2 *= 2) {
        int thisRowSum = powerOf2 - lastRowOnes;

        if (thisRowSum <= M && thisRowSum >= 0) {
            res += nCr[M][thisRowSum] * dp (row + 1, thisRowSum) % MOD;
            res %= MOD;
        }
    }

    return memo[row][lastRowOnes] = res;
}

int main() {
    cin >> N >> M;

    nCr[0][0] = 1;
    for (int i = 1; i <= M; i++) {
        nCr[i][0] = nCr[i][i] = 1;

        for (int j = 1; j < i; j++) {
            nCr[i][j] = (nCr[i - 1][j] + nCr[i - 1][j - 1]) % MOD;
        }
    }

    memset (memo, -1, sizeof (memo));
    long long res = 0;

    for (int i = 0; i <= M; i++) {
        res += dp (2, i) * nCr[M][i] % MOD;
        res %= MOD;
    }

    cout << res << "\n";
    return 0;
}