N,P = map(int,input().split())
dp = [0,0,1]+[0]*(N-2)
mod = 10**9+7
for i in range(3,N+1):
    dp[i] = P*dp[i-1]+dp[i-2]
    dp[i] %= mod

alsm = sum(dp)
ans = 0
for i in range(1,N+1):
    ans += dp[i]*alsm
    ans %= mod
    alsm -= dp[i]
    alsm %= mod
print(ans)