import sys

N,p = map(int,input().split())

s = 1
ds = 1

if N == 1:
    print (0)
    sys.exit()
elif N == 2:
    print (1)
    sys.exit()

a = 0
b = 1
mod = 10**9+7

for i in range(N-2):

    newb = b*p+a
    newa = b

    a = newa % mod
    b = newb % mod

    s += b
    ds += b**2
    s %= mod
    ds %= mod

print ((s**2+ds) * pow(2,mod-2,mod) % mod )