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#include <cassert>
#include <cstdint>
#include <cstring>
#include <algorithm>
#include <iostream>
#include <memory>
#include <string>
#include <vector>


typedef int16_t i16;
typedef int32_t i32;
typedef int64_t i64;

typedef uint8_t u8;

class Tab {
    i32 _rows;
    i32 _columns;
    std::unique_ptr<i32[]> _data;

    public:
    Tab(i32 rows, i32 columns)
        : _rows(rows), _columns(columns), _data(new i32[rows * columns])
    {}

    i32 * operator[](i32 row) { return row * _columns + _data.get(); }

    i32 & operator()(i32 row, i32 column) {
        return _data[row * _columns + column];
    }
};

i32 prime;

inline i32 normalize(i64 a) {
    return a % prime;
}

inline i32 add(i32 a, i32 b) {
    assert(0 <= a);
    assert(a < prime);
    assert(0 <= b);
    assert(b < prime);
    auto x = a + b;
    return (x > prime) ? x - prime : x;
}

inline i32 sub(i32 a, i32 b) {
    assert(0 <= a);
    assert(a < prime);
    assert(0 <= b);
    assert(b < prime);
    auto x = a - b;
    return (x < 0) ? x + prime : x;
}

int main()
{
    i32 n, m;
    std::cin >> n >> m >> prime;

    Tab Q(n, m+1);

    auto Q0 = Q[0];
    for (i32 j = 0; j <= m; j++) {
        auto q = (i64)j * ((i64)j + 1) / 2;
        Q0[j] = normalize(q);
    }

    for (i32 i = 1; i < n; i++) {
        auto Qi = Q[i];
        auto Qi_1 = Q[i-1];
        Qi[0] = 0;
        for (i32 j = 1; j <= m; j++) {
            auto qij = Qi[j-1];
            for (i32 k = 1; k <= j; k++) {
                // R(i-1, k, j)
                auto r = Qi_1[m];
                r = sub(r, Qi_1[k - 1]);
                r = sub(r, Qi_1[m - j]);
                qij = add(qij, r);
            }
            Qi[j] = qij;
        }
    }

    std::cout << Q(n-1, m);

    return 0;
}