#include<bits/stdc++.h>

using namespace std;

typedef vector<int> V;
typedef vector<V> VV;
typedef vector<VV> VVV;
int main(){
    int N,K;
    cin>>N>>K;K--;
    int M=1<<N;
    VVV dp(2,VV(N,V(M)));
    dp[0][K][1<<K]=1;
    V bits(M);
    iota(bits.begin(),bits.end(),0);
    sort(bits.begin(),bits.end(),[&](int l,int r){return __builtin_popcount(l)<__builtin_popcount(r);});
    for(auto &bit:bits){
        for(int k=0;k<N;k++){
            if(dp[0][k][bit]==0)continue;
            for(int l=0;l<N;l++)
                if((bit&(1<<l))==0){
                    if(k<l)dp[0][l][bit|(1<<l)]+=dp[0][k][bit];
                    else dp[1][l][bit|(1<<l)]+=dp[0][k][bit];
                }
        }
        for(int k=0;k<N;k++){
            if(dp[1][k][bit]==0)continue;
            for(int l=0;l<N;l++)
                if((bit&(1<<l))==0){
                    if(k<l)dp[1][l][bit|(1<<l)]+=dp[1][k][bit];
                }
        }
    }
    int res=0;
    for(int i=0;i<N;i++)
        res+=dp[1][i][M-1];
    cout<<res<<endl;
    return 0;
}