import std.algorithm;
import std.conv;
import std.range;
import std.stdio;
import std.string;

void main ()
{
	auto tests = readln.strip.to !(int);
	foreach (test; 0..tests)
	{
		auto n = readln.strip.to !(int);
		auto a = readln.splitter.map !(to !(int)).array;
		bool [int] b;
		foreach (i; 0..n)
		{
			foreach (j; i + 1..n)
			{
				b[a[j] - a[i]] = true;
			}
		}
		writeln (b.length);
	}
}
