#include<stdio.h>

FILE *f;

#define In "1-sir.in"
#define Out "1-sir.out"

#define M (255*256/2)

int sol[2][M];

int N,S,s,n,p,q;

#define abs(x) ((x)>0?(x):-(x))

int main()
 {
 f=fopen(In,"r");
 fscanf(f,"%d%d",&N,&S);
 sol[1][0]=1; S=abs(S);
 for(n=1;n<N;n++)
  {
  q=n%2; p=!q;
  for(s=0;s<=S;s++)
   sol[p][s]=sol[q][abs(s-n)]+sol[q][s+n];
  }
 freopen(Out,"w",f);
 fprintf(f,"%d\n",sol[p][S]);
 fclose(f);
 return 0;
 }