// #include <bits/allocator.h> // Temp fix for gcc13 global pragma
// #pragma GCC target("avx2,bmi2,popcnt,lzcnt")
// #pragma GCC optimize("O3,unroll-loops")
#include <bits/stdc++.h>
// #include <x86intrin.h>
using namespace std;
#if __cplusplus >= 202002L
using namespace numbers;
#endif
#ifdef LOCAL
	#include "Debug.h"
#else
	#define debug_endl() 42
	#define debug(...) 42
	#define debug2(...) 42
	#define debug_bin(...) 42
#endif



int main(){
	cin.tie(0)->sync_with_stdio(0);
	cin.exceptions(ios::badbit | ios::failbit);
	int n;
	cin >> n;
	vector<int> a(n);
	copy_n(istream_iterator<int>(cin), n, a.begin());
	ranges::sort(a | ranges::views::reverse);
	int64_t res = 0;
	for(auto i = 0; auto chunk: a | ranges::views::chunk_by(equal_to<>())){
		if((int)chunk.size() == 1){
			continue;
		}
		int x = *chunk.begin();
		while(a[i] >= 2 * x){
			++ i;
		}
		res += 1LL * (int)chunk.size() * ((int)chunk.size() - 1) / 2 * (n - i - (int)chunk.size());
	}
	cout << res << "\n";
	return 0;
}

/*

*/