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#include <iostream>
#include <array>
#include <vector>
#include <algorithm>

using ull = unsigned long long;

const int MAX_N = static_cast<int> (1e3 + 9);

unsigned N, K, p;

int collapseTime(std::vector<int> sequence, int sol = 0) {
    auto n = sequence.size();
    if(n == 1 || sol > K) {
        return sol;
    }

    std::vector<int> newSequence{};

    if(sequence[0] > sequence[1]) {
        newSequence.emplace_back(sequence[0]);
    }

    for(int i = 1; i < n - 1; ++i) {
        if(sequence[i] > sequence[i - 1] && sequence[i] > sequence[i + 1]) {
            newSequence.emplace_back(sequence[i]);
        }
    }

    if(sequence[n - 1] > sequence[n - 2]) {
        newSequence.emplace_back(sequence[n - 1]);
    }

    return collapseTime(newSequence, sol + 1);
};

int main() {
    std::cin >> N >> K >> p;

    std::vector<int> permutation{};

    for(int i = 1; i <= N; ++i) {
        permutation.emplace_back(i);
    }

    unsigned result = 0;

    do {
        if(collapseTime(permutation) == K) {
            ++result;
        }
    }
    while(std::next_permutation(permutation.begin(), permutation.end()));

    std::cout << result << std::endl;

    return 0;
}