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#include<bits/stdc++.h>
using namespace std;

#define int long long

#define PB push_back
#define MP make_pair
#define FI first
#define SE second
#define ST FI
#define ND SE
#define SZ(x) ((int)(x).size())

#define ALL(it, x) for(__typeof(x.begin()) it = x.begin(); it != x.end(); it++)
#define REP(i, x) for (int i = 0; i < x; i++)
#define FOR(i, x) for (int i = 1; i <= x; i++)
#define BACK(i, x) for (int i = x; i; i--)

typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<VI> VVI;

template<typename TH> void _dbg(const char* s, TH h) { cerr<<s<<"="<<h<<"\n"; }
template<typename TH, typename... TA> void _dbg(const char* s, TH h, TA... t) {
  while(*s != ',') {cerr<<*s++;} cerr<<"="<<h<<","; _dbg(s+1, t...);
}
#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#define debugv(x) {{cerr <<#x <<" = "; ALL(itt, (x)) cerr <<*itt <<", "; cerr <<"\n"; }}
#else
#define debug(...) (__VA_ARGS__)
#define debugv(x)
#define cerr if(0)cout
#endif

int n, k, p;
int res = 0;
vector<int> resv;
vector<int> data;

int solve(vector<int>& init_data) {
  int r = 0;
  vector<int> curr_data = init_data;
  while (curr_data.size() > 1) {
    vector<int> next_data;

    REP(i, (int)curr_data.size()) {
      if (!((i > 0 && curr_data[i - 1] > curr_data[i])
            || (i + 1 < (int)curr_data.size() && curr_data[i + 1] > curr_data[i]))) {
        next_data.PB(curr_data[i]);
      }
    }
    //debugv(next_data);
    swap(curr_data, next_data);

    r++;
  }
  return r;
}

int32_t main(){
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout << setprecision(7) << fixed;  
  cin >> n >> k >> p;

  resv.resize(2 * log2(n) + 5);
  data.resize(n);
  REP(i, n) {
    data[i] = i;
  }

  do {
    //debugv(data);
    int k1 = solve(data);

    //debug(k1);
    resv[k1]++;
  } while(next_permutation(data.begin(), data.end()));
  

  //debugv(resv);
  res = resv[k];
  cout << res << endl;
  return 0;
}