#include<fstream>
using namespace std;
ifstream in("1-sir.in");
ofstream out("1-sir.out");
const int N = 256;
const int V = 66000;
int ind[V],a[V],b[V];
int n,s,c;
int main(){
	int i;
	in>>n>>s;
	c=-32896;
	for(i=1;i<=65793;++i) ind[i]=c++;
	a[32897]=1;
	for(;n;--n){
		for(i=1;i<=65793;++i) if(a[i]){
			b[i-1]+=a[i];
			b[i+1]+=a[i];
		}
		for(i=1;i<=65793;++i){
			a[i]=b[i];
			b[i]=0;
		}
	}
	for(i=1;i<=65793;++i) if(ind[i]==s) out<<a[i];
	return 0;
}