#include <bits/stdc++.h>
#define rep(i, a, b) for (int i = a, I = b; i <= I; ++i)
#define per(i, a, b) for (int i = a, I = b; i >= I; --i)
using namespace std;
using i64 = long long;
using i128 = __int128_t;
template<typename T> void up(T &x, T y) { x < y ? x = y : 0; }
template<typename T> void down(T &x, T y) { x > y ? x = y : 0; }

const int N = 1000005;
int n, m, rk[N << 1], sa[N], tp[N << 1], tax[N];
int par[N], siz[N], s[N];
vector<int> e[N];
i64 cnt[N];

void radixSort() {
    for (int i = 1; i <= m; i++) tax[i] = 0;
    for (int i = 1; i <= n; i++) ++tax[rk[i]];
    for (int i = 1; i <= m; i++) tax[i] += tax[i - 1];
    for (int i = n; i >= 1; i--) sa[tax[rk[tp[i]]]--] = tp[i];
}
void suffixSort() {
    m = 0;
    for (int i = 1; i <= n; i++) rk[i] = s[i], tp[i] = i, m = max(m, s[i]);
    rep(i, 1, n) rk[i + n] = tp[i + n] = 0;
    radixSort();
    for (int len = 1, p; p < n; len <<= 1, m = p) {
        p = 0;
        for (int i = 1; i <= len; i++) tp[++p] = n - len + i;
        for (int i = 1; i <= n; i++) {
            if (sa[i] > len) {
                tp[++p] = sa[i] - len;
            }
        }
        radixSort(); swap(rk, tp); rk[sa[1]] = p = 1;
        for (int i = 2; i <= n; i++) {
            rk[sa[i]] = (tp[sa[i]] == tp[sa[i - 1]] && tp[sa[i] + len] == tp[sa[i - 1] + len]) ? p : ++p;
        }
    }
}

int find(int x) {
    while (x != par[x]) x = par[x] = par[par[x]];
    return x;
}
void merge(int u, int v, int t) {
    int x = find(u), y = find(v);
    cnt[siz[x]] -= t, cnt[siz[y]] -= t;
    par[x] = y, siz[y] += siz[x];
    cnt[siz[y]] += t;
}

void solve() {
    cin >> n;
    rep(i, 1, n) cin >> s[i];
    suffixSort();

    rep(i, 0, n) e[i].clear();
    rep(i, 1, n) par[i] = i, siz[i] = 1, cnt[i] = 0;
    for (int i = 1, k = 0; i <= n; ++i) {
        if (k) --k;
        if (rk[i] == 1) continue;
        int j = sa[rk[i] - 1];
        while (max(i, j) + k <= n && s[i + k] == s[j + k]) ++k;
        e[k].push_back(rk[i]);
    }
    per(i, n, 1) {
        for (auto pos : e[i]) merge(pos - 1, pos, i);
    }
    cnt[1] = 1ll * n * (n + 1) / 2;
    rep(i, 2, n) cnt[1] -= cnt[i] * i;

    i64 ans = 0;
    priority_queue<i64, vector<i64>, greater<i64>> pq;
    int last = -1;
    rep(i, 1, n) {
        if (!cnt[i]) continue;
        if (~last) {
            ans += last + i;
            --cnt[i];
            if (last + i <= n) ++cnt[last + i];
            else pq.push(last + i);
            last = -1;
        }
        i64 cur = cnt[i] / 2;
        ans += cur * i * 2;
        cnt[i] -= cur * 2;
        if (i * 2 <= n) cnt[i * 2] += cur;
        else while (cur--) pq.push(i * 2);
        if (cnt[i]) last = i;
    }
    if (~last) pq.push(last);
    while ((int) pq.size() > 1) {
        i64 x = pq.top(); pq.pop();
        i64 y = pq.top(); pq.pop();
        ans += x + y, pq.push(x + y);
    }

    i64 ans1 = 1ll * n * (n + 1) / 2;
    i64 g = __gcd(ans, ans1);
    ans /= g, ans1 /= g;
    if (ans1 == 1) cout << ans << "\n";
    else cout << ans << "/" << ans1 << "\n";
}

int main() {
	ios::sync_with_stdio(0), cin.tie(0);

    int T; cin >> T;
    while (T--) solve();    

	return 0;
}