a = input().strip().split() n = int(a[0]) m = int(a[1]) resArr= [0 for x in range(m+1)] for i in range(1,n+1): for j in range(m,0,-1): if i < j: resArr[j] = resArr[j]+resArr[j-i] elif i > j: resArr[j] = resArr[j] elif i == j: resArr[j] = resArr[j]+1 print(resArr[m])