# https://yukicoder.me/problems/no/978

MOD = 10 ** 9 + 7

def main():
    N, p = map(int ,input().split())

    fib = [0] * (N +1)
    fib[1] = 0
    fib[2] = 1
    for n in range(3, N +1):
        ans = p * fib[n - 1]
        ans %= MOD
        ans += fib[n - 2]
        ans %= MOD

        fib[n] = ans
    
    cum_fib_list = [0] * (N + 1)
    cum_fib = 0
    for i in range(N + 1):
        cum_fib += fib[i]
        cum_fib %= MOD
        cum_fib_list[i] = cum_fib
    
    answer = 0
    for i in range(1, N + 1):
        a = fib[i]
        cum_a = cum_fib_list[i]

        ans = (a * cum_a) % MOD
        answer += ans
        answer %= MOD
    print(answer)





if __name__ == "__main__":
    main()