def mat_mul(A, B):
    C = [[0]*len(B[0]) for _ in range(len(A))]
    
    for i in range(len(A)):
        for j in range(len(B[0])):
            for k in range(len(A[0])):
                C[i][j] += A[i][k]*B[k][j]
                C[i][j] %= MOD
    
    return C

N, p = map(int, input().split())
MOD = 10**9+7
A = [[p, 1], [1, 0]]
arr = [[1], [0]]
acc = 1
ans = 1

for _ in range(N-2):
    arr = mat_mul(A, arr)
    ai = arr[0][0]
    acc += ai
    acc %= MOD
    ans += acc*ai
    ans %= MOD

print(ans)