MOD = 1000000007
N, p = map(int,input().split())
S = [0,1]
a, b = 0, 1
for k in range(N):
    t = p*b + a
    t %= MOD
    a, b = b, t
    S.append(t)

T = [0 for k in range(N)]
for k in range(N):
    T[k] = T[k-1] + S[k]
    T[k] %= MOD

ans = S[0]*T[-1]
ans %= MOD
for k in range(1,N):
    ans += S[k]*(T[-1]-T[k-1])
    ans %= MOD
print(ans)