using namespace std;

#include <cstdio>

#define FIN "1-sir.in"
#define FOUT "1-sir.out"
#define NMAX 27
#define SMAX 27*128

int s[NMAX][SMAX], N, S;
const int prim = 194767;

int
 main ()
{
  int jj;
  
  freopen (FIN, "rt", stdin);
  freopen (FOUT, "wt", stdout);

  scanf ("%d%d", &N, &S);
  s[1][0] = 1;
  for (int i = 2; i <= N; ++ i)
    for (int j = 0; j <= N*(N-1)/2; ++ j)
     {
       jj = j - (i-1) > 0 ? j - (i-1) : -j + (i-1);
       s[i][j] = s[i-1][jj] + s[i-1][j + (i-1)];
     }
  printf ("%d\n", s[N][S]);
  return 0;
}