#include <bits/stdc++.h>

int ri() {
	int n;
	scanf("%d", &n);
	return n;
}
#define MOD 1000000007
int main() {
	int n = ri();
	int p = ri();
	if (n == 1) {
		puts("0");
		return 0;
	}
	int a[n];
	a[0] = 0;
	a[1] = 1;
	for (int i = 2; i < n; i++) a[i] = ((int64_t) a[i - 1] * p + a[i - 2]) % MOD;
	int sum = 0;
	int res = 0;
	for (int i = 0; i < n; i++) {
		sum += a[i];
		if (sum >= MOD) sum -= MOD;
		res = (res + (int64_t) sum * a[i]) % MOD;
	}
	printf("%d\n", res);
  	return 0;
}