n, p = map(int, input().split())
MOD = 10**9 + 7

if n == 1:
    print(0)
    exit()

a = [0] * n
a[1] = 1
for i in range(2, n):
    a[i] = p * a[i - 1] + a[i - 2]
    a[i] %= MOD

diag = 0
for i in range(n):
    diag += a[i] * a[i]
    diag %= MOD
sum_a = sum(a) % MOD
ans = ((sum_a * sum_a) - diag) * pow(2, MOD - 2, MOD) + diag

print(ans % MOD)