There is a building with n rooms, numbered 1 to n.

We can move from any room to any other room in the building.

Let us call the following event a move: a person in some room i goes to another room j~ (i \neq j).

Initially, there was one person in each room in the building.

After that, we know that there were exactly k moves happened up to now.

We are interested in the number of people in each of the n rooms now. How many combinations of numbers of people in the n rooms are possible?

Find the count modulo (10^9 + 7).

Constraints

* All values in input are integers.
* 3 \leq n \leq 2 \times 10^5
* 2 \leq k \leq 10^9

Input

Input is given from Standard Input in the following format:


n k


Output

Print the number of possible combinations of numbers of people in the n rooms now, modulo (10^9 + 7).

Examples

Input

3 2


Output

10


Input

200000 1000000000


Output

607923868


Input

15 6


Output

22583772
def inv(a,m=10**9+7):
    b=m
    (x, lastx) = (0, 1)
    (y, lasty) = (1, 0)
    while b != 0:
        q = a // b
        (a, b) = (b, a % b)
        (x, lastx) = (lastx - q * x, x)
        (y, lasty) = (lasty - q * y, y)
    return lastx % m

mod=10**9+7
n,k=map(int,input().split())
k=min(k,n-1)
frac=[1]
for i in range(1,n+1):
    frac.append(frac[-1]*i%mod)

ans=0
for i in range(k+1):
    tmp=inv(frac[i]**2%mod*frac[n-i]*frac[n-1-i]%mod)
    ans+=tmp
    ans%=mod
ans=ans*frac[n]*frac[n-1]%mod
print(ans)