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#include <cstdio>
#include <cstdlib>
#include <cstdint>

#include <numeric>
#include <vector>
#include <set>

using permutation_t = std::vector<int>;

static const uint64_t MODULUS = 1000 * 1000 * 1000 + 7;

uint64_t count_inversions(const permutation_t& p) {
    uint64_t total = 0;
    for (int i = 0; i < p.size(); i++) {
        for (int j = i + 1; j < p.size(); j++) {
            if (p[i] > p[j]) {
                ++total;
            }
        }
    }
    return total;
}

permutation_t compose_perms(const permutation_t& a, const permutation_t& b) {
    permutation_t ret;
    ret.reserve(a.size());
    for (int i = 0; i < a.size(); i++) {
        ret.push_back(a[b[i]]);
    }
    return ret;
}

uint64_t modular_inverse(int64_t a, int64_t b) {
    int64_t oldr = a;
    int64_t r = b;
    int64_t olds = 1;
    int64_t s = 0;

    while (r != 0) {
        const int64_t q = oldr / r;
        const int64_t newr = oldr - q * r;
        const int64_t news = olds - q * s;
        oldr = r;
        olds = s;
        r = newr;
        s = (news + b) % b;
    }

    // printf("modular inverse: %lld\n", olds);

    return olds;
}

int main() {
    // Read data
    int n, k;
    scanf("%d %d", &n, &k);

    std::vector<permutation_t > generators;
    generators.reserve(n);

    for (int i = 0; i < k; i++) {
        permutation_t p;
        p.reserve(k);
        for (int j = 0; j < n; j++) {
            int x;
            scanf("%d", &x);
            p.push_back(x - 1);
        }
        generators.push_back(std::move(p));
    }

    // Generate all permutations from the elements
    using permutation_set_t = std::set<permutation_t>;
    permutation_set_t allperms;

    permutation_t identity(n);
    std::iota(identity.begin(), identity.end(), 0);
    allperms.insert(std::move(identity));

    std::vector<permutation_set_t::iterator> hot_items;
    hot_items.push_back(allperms.begin());

    while (!hot_items.empty()) {
        auto it = hot_items.back();
        hot_items.pop_back();

        for (const auto& genperm : generators) {
            auto newp = compose_perms(genperm, *it);
            auto [newit, inserted] = allperms.emplace(std::move(newp));
            if (inserted) {
                hot_items.push_back(newit);
            }
        }
    }

    // Count inversions
    uint64_t inversions = 0;
    for (const auto& p : allperms) {
        // for (int i : p) {
        //     printf("%d ", i);
        // }
        // printf(": %lld\n", count_inversions(p));
        inversions = (inversions + count_inversions(p)) % MODULUS;
    }

    inversions = (inversions * modular_inverse(allperms.size(), MODULUS)) % MODULUS;
    printf("%llu\n", inversions);

    return 0;
}