#include<iostream>
#include<cstring>
#include<queue>
#include<vector>
#include<algorithm>
#include<cstdio>
#define MAX_N 2000006
using namespace std;

typedef long long ll;

int a[MAX_N];
int n;

int T;
const int mod=10000007;

int cnt[MAX_N];

ll Pow(ll a,ll b) {
    ll res = 1;
    while (b) {
        if (b & 1)res = res * a % mod;
        b >>= 1;
        a = a * a % mod;
    }
    return res;
}

ll ways[MAX_N];
int k;

int main() {
    scanf("%d", &T);
    while (T--) {
        int maxA = -1;
        memset(a, 0, sizeof(a));
        memset(cnt, 0, sizeof(cnt));
        memset(ways, 0, sizeof(ways));
        scanf("%d%d", &n, &k);
        for (int i = 0; i < n; i++) {
            int t;
            scanf("%d", &t);
            maxA = max(maxA, t);
            a[t]++;
        }
        for (int i = 1; i <= maxA; i++)
            for (int j = 1; j * i <= maxA; j++)
                cnt[i] += a[i * j];
        for (int i = 1; i <= maxA; i++)
            ways[i] = (Pow(2, cnt[i]) - 1 + mod) % mod;
        for (int i = maxA; i >= 1; i--)
            for (int j = 2; j * i <= maxA; j++)
                ways[i] = (ways[i] - ways[i * j] + mod) % mod;
        ll ans = 0;
        for (int i = 1; i <= maxA; i++)
            ans = (ans + ways[i] * Pow(i, k)) % mod;
        printf("%lld", ans);
        if(T!=0)printf("\n");
    }
    return 0;
}