# Enter your code here. Read input from STDIN. Print output to STDOUT
import math

n, k = map(int, input().split())

def combi(n, r):
    if r == 0 or r == n:
        return(1)
    s, r = 1, (n-r if n-r < r else r)
    for i in range(r):
        s *= ((n-i) / (i+1))
    return(math.ceil(s))
 
c = 0
for i in range(1, n+1):
    for j in range(i+1):
        if combi(i, j) > k:
            c += 1

print(c)