P, K = map(int, input().split())
mod = 10 ** 9 + 7
pre0, pre1 = 1, 0
for i in range(K):
    dp0 = (P + 1) * pre0 + 2 * pre1
    dp1 = (P - 1) * pre0 + (2 * P - 2) * pre1
    dp0 %= mod
    dp1 %= mod
    dp0, pre0 = pre0, dp0
    dp1, pre1 = pre1, dp1
print(pre0)