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#include <bits/stdc++.h>
#define ll long long
#define st first
#define nd second
#define mk std::make_pair
#define debug if(0)

ll p;
ll n, m;
std::vector<std::vector<ll> > dp0;
std::vector<std::vector<ll> > dp1;

// sum1[i][m] = sum{1, m}(dp0[i][m]/m), dp[i][0] = 0 dla wszystkich i
std::vector<std::vector<ll> > sum1; 
// sum2[i][m] = sum{1, m}( (dp0[i][m] + dp1[i][m]) * m), dp[i][0] = 0 dla wszystkich i
std::vector<std::vector<ll> > sum2;
// sum3[i][m] = sum{1, m}( dp0[i][m] + dp1[i][m] ), dp[i][0] = 0 dla wszystkich i
std::vector<std::vector<ll> > sum3;
// sum4[i][m] = sum{1, m}( sum3[i][m] )
std::vector<std::vector<ll> > sum4;

void prepare(std::vector<std::vector<ll> > &v) {
    v.clear();
    v.reserve(n+5);
    std::vector<ll> tmp;
    tmp.reserve(m+5);
    for (int i = 0; i <= m+3; i++)
        tmp.push_back(0);
    for (int i = 0; i <= n+3; i++)
        v.push_back(tmp);
}

void input() {
    std::cin >> n >> m >> p;
    // teraz wszystkie tablice musza miec wymiary n x m
    prepare(dp0);
    prepare(dp1);
    prepare(sum1);
    prepare(sum2);
    prepare(sum3);
    prepare(sum4);
}

void base_cases() {
    // dp0[1][x], dp0[2][x], dp1[1][x], dp1[2][x] dla kazdego x \in [1, m]
    // dp0[1][x] = x, dp1[1][x] = 0
    for (ll x = 1; x <= m; x++) {
        dp0[1][x] = x;
    
        sum2[1][x] = (sum2[1][x-1] + ((dp0[1][x] * x)%p)) % p;
        sum3[1][x] = (sum3[1][x-1] + dp0[1][x]) % p;

        sum4[1][x] = (sum4[1][x-1] + sum3[1][x]) % p;

        debug std::cout << "sum4[1][" << x << "] = " << sum4[1][x] << "\n";
    }
    // dp0[2][x] - >= x, x
    // dp0[2][x] = (m-x+1) * x^2
    for (ll x = 1; x <= m; x++) {
        ll a = m-x+1;
        ll b = x * x;
        a %= p; b %= p;
        dp0[2][x] = (a*b) % p;

        sum1[2][x] = (sum1[2][x-1] + ((a*x)%p)) % p;
    }
    // dp1[2][x] - <x, x
    // dp1[2][x] = (x-1)^2 + (x-2)^2 + ... + 2^2 + 1^2 = [(x-1)x(2(x-1) + 1)]/6
    for (ll x = 1; x <= m; x++) {
        ll a = x-1;
        ll b = x;
        ll c = 2*(x-1) + 1;
        if (a % 2 == 0)
            a /= 2;
        else
            b /= 2;
        if (a % 3 == 0)
            a /= 3;
        else if (b % 3 == 0)
            b /= 3;
        else
            c /= 3;
        ll tmp = (a * b) % p;
        tmp = (tmp * c) % p;
        dp1[2][x] = tmp;       

        sum2[2][x] = (sum2[2][x-1] + ( ((dp0[2][x] + dp1[2][x]) * x) % p )) % p;
        sum3[2][x] = (sum3[2][x-1] + ( dp0[2][x] + dp1[2][x] )) % p;

        sum4[2][x] = (sum4[2][x-1] + sum3[2][x]) % p;
    }
}

void count_dp() {
    for (int i = 3; i <= n; i++) {
        // dp0[i][x] dla kazdego x
        for (ll x = 1; x <= m; x++) {
            // dp0[i][x] = A + B + C
            // A = [ sum{x' = x, m} [ dp0[i-1][x']/x' ] ] * x^2 = x^2 * [ sum1[i-1][m] - sum1[i-1][x-1] ]
            // B = [ sum{x'' = 1, x-1} [ (dp0[i-2][x''] + dp1[i-2][x'']) * x'' ] ] * (m-x+1) * x = (m-x+1) * x * [ sum2[i-2][x-1] ]
            // C = [ sum{x' = x, m} [ sum3[i-2][m'-1] ] - (m-x+1) * sum3[i-2][x-1] ] * x^2 =
            // = [ (sum4[i-2][m-1] - sum4[i-2][x-1] ) - (m-x+1) * sum3[i-1][x-1] ] * x^2

            // A
            ll a = (x*x) % p;
            ll b = (sum1[i-1][m] - sum1[i-1][x-1]) % p;
            b = (b + p) % p;
            ll A = (a * b) % p;

            ll AA = (x * b) % p;

            debug {
                std::cout << "licze dp0[" << i << "][" << x << "], konkretnie A:\n";
                std::cout << "a = " << a << "\n";
                std::cout << "b = " << b << "\n";
                std::cout << "A = " << A << "\n";
            }

            // B 
            a = (m-x+1);
            b = x;
            ll c = sum2[i-2][x-1];
            ll B = (a * b) % p;
            B = (B * c) % p;

            ll BB = (a * c) % p;

            debug std::cout << "B = " << B << "\n";

            // C
            if (x == 1) 
                a = (sum4[i-2][m-1] - sum4[i-2][x-1]) % p; 
            else
                a = (sum4[i-2][m-1] - sum4[i-2][x-2]) % p;
            a = (a + p) % p;

            debug std::cout << "sum4[" << i-2 << "][" << m-1 << "] - sum4[" << i-2 << "][" << x-1 << "] = " << a << "\n";

            b = (m-x+1);
            b = (b * sum3[i-2][x-1]) % p;

            debug std::cout << "(" << m-x+1 << ") * sum3[" << i-2 << "][" << x-1 << "] = " << b << "\n";

            a = (a - b) % p;
            a = (a + p) % p;
            c = (x * x) % p;
            ll C = (a * c) % p;

            ll CC = (a * x) % p;

            debug std::cout << "C = " << C << "\n";
            // dp0[i][x]
            dp0[i][x] = (A + B + C) % p;

            sum1[i][x] = (sum1[i][x-1] + (AA + BB + CC)) % p;
        }
        // dp1[i][x] dla kazdego x
        for (ll x = 1; x <= m; x++) {
            // dp1[i][x] = sum{x' < x} [ (dp0[i-1][x'] + dp1[i-1][x']) * x' ] = sum2[i-1][x-1]
            dp1[i][x] = sum2[i-1][x-1];

            sum2[i][x] = (sum2[i][x-1] + ( (( dp0[i][x] + dp1[i][x] ) * x) % p) ) % p;
            sum3[i][x] = (sum3[i][x-1] + ( dp0[i][x] + dp1[i][x] )) % p;

            sum4[i][x] = (sum4[i][x-1] + sum3[i][x]) % p;
        }
    }
}

int main() {
    std::ios_base::sync_with_stdio(0); std::cin.tie(NULL);
    input();
    base_cases();
    count_dp();
    
    ll res = 0;
    for (int x = 1; x <= m; x++) {
        res = (res + dp0[n][x]) % p;
        res = (res + dp1[n][x]) % p;
    }

    debug {
        std::cout << "Wyniki dp:\n";
        for (int i = 1; i <= n; i++) {
            for (int x = 1; x <= m; x++) {
                std::cout << "dp0[" << i << "][" << x << "] = " << dp0[i][x] << "\n";
                std::cout << "dp1[" << i << "][" << x << "] = " << dp1[i][x] << "\n";
            }
        }
    }

    std::cout << res << "\n";
}