import java.io.*;
import java.util.*;

public class Main {
    static FastScanner in;
    static int q;

    public static void main(String[] args) throws IOException {
        //        System.setOut(new PrintStream(new BufferedOutputStream(new FileOutputStream("nocross.out")), true));
        in = new FastScanner(System.in);
        //        in = new FastScanner("nocross.in");
        //        in = new FastScanner("input.txt");
        q = in.nextInt();
        while (q-- > 0) {
            long n = in.nextLong();
            long c = in.nextLong();
            if (c == n * (n - 1) / 2) {
                for (long i = n; i >= 1; i--) {
                    System.out.print(i + " ");
                }
            } else if (n % 2 == 0) {
                if (c == n * n / 4) {
                    System.out.print(n / 2 + " ");
                    for (int i = 1; i <= n; i++) {
                        if (i != n / 2)
                            System.out.print(i + " ");
                    }
                } else {
                    System.out.println(-1);
                }
            } else {
                if (c == (n - 1) * (n + 1) / 4) {
                    System.out.print((n + 1) / 2 + " ");
                    for (int i = 1; i <= n; i++) {
                        if (i != (n + 1) / 2)
                            System.out.print(i + " ");
                    }
                } else {
                    System.out.println(-1);
                }
            }
            System.out.println();
        }
    }
}

class FastScanner {

    BufferedReader br;
    StringTokenizer tokenizer;

    FastScanner(String fileName) throws FileNotFoundException {
        this(new FileInputStream(new File(fileName)));
    }

    FastScanner(InputStream is) {
        br = new BufferedReader(new InputStreamReader(is));
    }

    String nextLine() throws IOException {
        tokenizer = null;
        return br.readLine();
    }

    String next() throws IOException {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            String line = br.readLine();
            if (line == null) {
                return null;
            }
            tokenizer = new StringTokenizer(line);
        }
        return tokenizer.nextToken();
    }

    int nextInt() throws IOException {
        return Integer.parseInt(next());
    }

    long nextLong() throws IOException {
        return Long.parseLong(next());
    }

    char nextChar() throws IOException {
        return next().charAt(0);
    }
}