# problem 2
P, K = map(int, input().split())
# dp[K] = K 回目の操作を終えた時に　mod P で 0
# ex_dp[K] = K 回目の操作を終えた時に mod P で　0 でない
dp = [0 for i in range(K+1)]
ex_dp = [0 for i in range(K+1)]
dp[0] = 1
mod = 10**9 + 7
for i in range(1, K+1):
    dp[i] = dp[i-1]*(P+1) + ex_dp[i-1]*2
    ex_dp[i] = dp[i-1]*(P-1) + ex_dp[i-1]*(2*P-2)
    dp[i] %= mod
    ex_dp[i] %= mod
ans = dp[K]
print(ans)