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

p = 10 ** 9 + 7
N = 10 ** 5 *5  # N は必要分だけ用意する
fact = [1, 1]  # fact[n] = (n! mod p)
factinv = [1, 1]  # factinv[n] = ((n!)^(-1) mod p)
inv = [0, 1]  # factinv 計算用

for i in range(2, N + 3):
    fact.append((fact[-1] * i) % p)
    inv.append((-inv[p % i] * (p // i)) % p)
    factinv.append((factinv[-1] * inv[-1]) % p)

def cmb(n, r, p):
    if (r < 0) or (n < r):
        return 0
    r = min(r, n - r)
    return fact[n] * factinv[r] * factinv[n-r] % p

ans = 0
if k < n:
    for i in range(k+1):
        ans += cmb(n,i,p)*cmb(n-1,n-i-1,p)
        ans %= p
else:
    for i in range(n):
        ans += cmb(n,i,p)*cmb(n-1,n-i-1,p)
        ans %= p

print(ans) n,k = map(int, input().split()) n map(int, input().split()) map int input().split() ().split () input split k p = 10 ** 9 + 7 p 10 ** 9 + 7 10 ** 9 10 9 7 N = 10 ** 5 *5 N 10 ** 5 *5 10 ** 5 10 5 5 fact = [1, 1] fact [1, 1] 1 1 factinv = [1, 1] factinv [1, 1] 1 1 inv = [0, 1] inv [0, 1] 0 1 for i in range(2, N + 3):
    fact.append((fact[-1] * i) % p)
    inv.append((-inv[p % i] * (p // i)) % p)
    factinv.append((factinv[-1] * inv[-1]) % p) i range(2, N + 3) range 2 N + 3 N 3 fact.append((fact[-1] * i) % p) fact.append fact append (fact[-1] * i) % p fact[-1] * i fact[-1] fact -1 i p inv.append((-inv[p % i] * (p // i)) % p) inv.append inv append (-inv[p % i] * (p // i)) % p -inv[p % i] * (p // i) -inv[p % i] inv[p % i] inv p % i p i p // i p i p factinv.append((factinv[-1] * inv[-1]) % p) factinv.append factinv append (factinv[-1] * inv[-1]) % p factinv[-1] * inv[-1] factinv[-1] factinv -1 inv[-1] inv -1 p def cmb(n, r, p):
    if (r < 0) or (n < r):
        return 0
    r = min(r, n - r)
    return fact[n] * factinv[r] * factinv[n-r] % p cmb if (r < 0) or (n < r):
        return 0
     (r < 0) or (n < r) r < 0 r 0 n < r n r return 0 0 r = min(r, n - r) r min(r, n - r) min r n - r n r return fact[n] * factinv[r] * factinv[n-r] % p fact[n] * factinv[r] * factinv[n-r] % p fact[n] * factinv[r] * factinv[n-r] fact[n] * factinv[r] fact[n] fact n factinv[r] factinv r factinv[n-r] factinv n-r n r p n n r r p p ans = 0 ans 0 if k < n:
    for i in range(k+1):
        ans += cmb(n,i,p)*cmb(n-1,n-i-1,p)
        ans %= p
else:
    for i in range(n):
        ans += cmb(n,i,p)*cmb(n-1,n-i-1,p)
        ans %= p k < n k n for i in range(k+1):
        ans += cmb(n,i,p)*cmb(n-1,n-i-1,p)
        ans %= p i range(k+1) range k+1 k 1 ans += cmb(n,i,p)*cmb(n-1,n-i-1,p) ans cmb(n,i,p)*cmb(n-1,n-i-1,p) cmb(n,i,p) cmb n i p cmb(n-1,n-i-1,p) cmb n-1 n 1 n-i-1 n-i n i 1 p ans %= p ans p for i in range(n):
        ans += cmb(n,i,p)*cmb(n-1,n-i-1,p)
        ans %= p i range(n) range n ans += cmb(n,i,p)*cmb(n-1,n-i-1,p) ans cmb(n,i,p)*cmb(n-1,n-i-1,p) cmb(n,i,p) cmb n i p cmb(n-1,n-i-1,p) cmb n-1 n 1 n-i-1 n-i n i 1 p ans %= p ans p print(ans) print ans n,k = map(int, input().split()) map(int, input().split()) n inv = [0, 1] [0, 1] inv def cmb(n, r, p):
    if (r < 0) or (n < r):
        return 0
    r = min(r, n - r)
    return fact[n] * factinv[r] * factinv[n-r] % p def cmb(n, r, p):
    if (r < 0) or (n < r):
        return 0
    r = min(r, n - r)
    return fact[n] * factinv[r] * factinv[n-r] % p cmb k = map(int, input().split()) map(int, input().split()) k N = 10 ** 5 *5 10 ** 5 *5 N ans %= p p ans ans %= p p ans ans = 0 0 ans p = 10 ** 9 + 7 10 ** 9 + 7 p ans += cmb(n,i,p)*cmb(n-1,n-i-1,p) cmb(n,i,p)*cmb(n-1,n-i-1,p) ans factinv = [1, 1] [1, 1] factinv fact = [1, 1] [1, 1] fact ans += cmb(n,i,p)*cmb(n-1,n-i-1,p) cmb(n,i,p)*cmb(n-1,n-i-1,p) ans
n,k = map(int, input().split())

p = 10 ** 9 + 7
N = 10 ** 5 *5  # N は必要分だけ用意する
fact = [1, 1]  # fact[n] = (n! mod p)
factinv = [1, 1]  # factinv[n] = ((n!)^(-1) mod p)
inv = [0, 1]  # factinv 計算用

for i in range(2, N + 3):
    fact.append((fact[-1] * i) % p)
    inv.append((-inv[p % i] * (p // i)) % p)
    factinv.append((factinv[-1] * inv[-1]) % p)

def cmb(n, r, p):
    if (r < 0) or (n < r):
        return 0
    r = min(r, n - r)
    return fact[n] * factinv[r] * factinv[n-r] % p

ans = 0
if k < n:
    for i in range(k+1):
        ans += cmb(n,i,p)*cmb(n-1,n-i-1,p)
        ans %= p
else:
    for i in range(n):
        ans += cmb(n,i,p)*cmb(n-1,n-i-1,p)
        ans %= p

print(ans)
