#include <stdio.h>

int n, s, a1[65000], a2[65000];

int ab(int x) { return x >= 0 ? x : (-x);}

int main()
{
	freopen("1-sir.in","r",stdin);
	freopen("1-sir.out","w",stdout);

	int i, j, k, m;
	scanf("%d %d",&n,&s);
	m = (n * (n - 1)) / 2;

	a1[0] = 1;

	for (i = 1; i <= n; i++)
	{
		for (j = 0; j <= m; j++)		
			a2[j] = a1[ab(j - i + 1)] + a1[ab(j + i - 1)];
		for (j = 0; j <= m; j++) a1[j] = a2[j];
	}

	printf("%d\n",a1[ab(s)] / 2);
	return 0;
}