#include<iostream>
#include<fstream>
#define max_N 2
#define max_S 33000

using namespace std;

ifstream fin("1-sir.in");
ofstream fout("1-sir.out");

int N, S, D[max_N][max_S], i, j, k;

int main()
{
    fin >> N >> S;
    D[0][0] = 1;
    D[0][1] = 1;
    for(i = 1; i < N ; i ++)
    {
        for(j = 1; j <= N*(N-1)/2; j ++)
            D[1][j] = D[0][j + (i - 1)] + D[0][j - (i - 1)];

        for (k = 0; k <= N*(N-1)/2 ; k ++)
        {
            D[0][k] = D[1][k];
            D[1][k] = 0;
        }
    }
    fout << D[0][abs(S)]-1;
    return 0;
}