import java.io.BufferedReader import java.io.InputStream import java.io.InputStreamReader import java.util.* import kotlin.math.abs import kotlin.math.max import kotlin.math.min val MOD = 1_000_000_007 class Solver(stream: InputStream, private val out: java.io.PrintWriter) { fun solve() { val N = ni() val p = ni() if (N == 1) { out.println("0") return } val A = LongArray(N) A[0] = 0 A[1] = 1 for (i in 2 until N) { A[i] = (A[i - 1] * p % MOD + A[i - 2]) % MOD } val cum = LongArray(N + 1) for (i in 0 until N) { cum[i + 1] = (cum[i] + A[i]) % MOD } var ans = 0L for (i in 0 until N) { ans += A[i] * cum[i + 1] % MOD } out.println(ans % MOD) } private val isDebug = try { // なんか本番でエラーでる System.getenv("MY_DEBUG") != null } catch (t: Throwable) { false } private var tokenizer: StringTokenizer? = null private val reader = BufferedReader(InputStreamReader(stream), 32768) private fun next(): String { while (tokenizer == null || !tokenizer!!.hasMoreTokens()) { tokenizer = StringTokenizer(reader.readLine()) } return tokenizer!!.nextToken() } private fun ni() = next().toInt() private fun nl() = next().toLong() private fun ns() = next() private fun na(n: Int, offset: Int = 0): IntArray { return map(n, offset) { ni() } } private inline fun map(n: Int, offset: Int = 0, f: (Int) -> Int): IntArray { val res = IntArray(n) for (i in 0 until n) { res[i] = f(i + offset) } return res } private inline fun debug(msg: () -> String) { if (isDebug) System.err.println(msg()) } private fun debug(a: LongArray) { debug { a.joinToString(" ") } } private fun debug(a: IntArray) { debug { a.joinToString(" ") } } private fun debug(a: BooleanArray) { debug { a.map { if (it) 1 else 0 }.joinToString("") } } private fun debugDim(A: Array) { if (isDebug) { for (a in A) { debug(a) } } } /** * 勝手にimport消されるのを防ぎたい */ private fun hoge() { min(1, 2) max(1, 2) abs(-10) } } fun pair(a: A, b: B) = RPair(a, b) data class RPair(val _1: A, val _2: B) fun main() { val out = java.io.PrintWriter(System.out) Solver(System.`in`, out).solve() out.flush() }