n,m = map(int,input().split())
ans = 1
now = 1
ok = True
for i in range(n-1):
    now *= 2
    if now > m:
        ok = False
        break
    ans += now
if ok:
    print(ans)
    exit()

ans = m
now = m
for i in range(n-1):
    now = (now+1)//2
    ans += now
    if now == 1:
        print(ans+(n-2-i))
        exit()

print(ans)