import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;

public class B {
	InputStream is;
	PrintWriter out;
	String INPUT = "";
	
	void solve()
	{
		int[] dp = new int[100005];
		dp[1] = 0;
		for(int i = 2;i < dp.length;i++){
			dp[i] = i-1 + dp[i/2] + dp[(i-1)/2];
		}
		for(int Q = ni();Q > 0;Q--){
			long n = ni(), c = ni();
			long inf = dp[(int)n], sup = n*(n-1)/2;
			if(inf <= c && c <= sup){
				int[] ret = new int[(int)n];
				dfs(0, (int)n, 0, (int)n, c, dp, ret);
				for(int i = 0;i < n;i++){
					out.print(ret[i]+1 + " ");
				}
				out.println();
			}else{
				out.println(-1);
			}
		}
	}
	
	void dfs(int low, int high, int l, int r, long c, int[] dp, int[] a)
	{
		if(high-low <= 0)return;
		if(high-low == 1){
			a[l] = low;
			return;
		}
		for(int k = 0;k <= high-low-1;k++){
			if(dp[k] + dp[high-low-1-k] <= c-(high-low-1) &&
					c-(high-low-1) <= (long)k*(k-1)/2+(long)(high-low-1-k)*(high-low-1-k-1)/2){
				a[l] = k + low;
				long lv = dp[k], rv = c-(high-low-1)-dp[k];
				if(rv > (long)(high-low-1-k)*(high-low-1-k-1)/2){
					rv = (long)(high-low-1-k)*(high-low-1-k-1)/2;
					lv = c-(high-low-1)-dp[k];
				}
				dfs(low, k+low, l+1, l+k+1, lv, dp, a);
				dfs(k+low+1, high, l+k+1, r, rv, dp, a);
				return;
			}
		}
		throw new RuntimeException();
	}
	
	void run() throws Exception
	{
		is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes());
		out = new PrintWriter(System.out);
		
		long s = System.currentTimeMillis();
		solve();
		out.flush();
		if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms");
	}
	
	public static void main(String[] args) throws Exception { new B().run(); }
	
	private byte[] inbuf = new byte[1024];
	public int lenbuf = 0, ptrbuf = 0;
	
	private int readByte()
	{
		if(lenbuf == -1)throw new InputMismatchException();
		if(ptrbuf >= lenbuf){
			ptrbuf = 0;
			try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }
			if(lenbuf <= 0)return -1;
		}
		return inbuf[ptrbuf++];
	}
	
	private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }
	private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }
	
	private double nd() { return Double.parseDouble(ns()); }
	private char nc() { return (char)skip(); }
	
	private String ns()
	{
		int b = skip();
		StringBuilder sb = new StringBuilder();
		while(!(isSpaceChar(b))){ // when nextLine, (isSpaceChar(b) && b != ' ')
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}
	
	private char[] ns(int n)
	{
		char[] buf = new char[n];
		int b = skip(), p = 0;
		while(p < n && !(isSpaceChar(b))){
			buf[p++] = (char)b;
			b = readByte();
		}
		return n == p ? buf : Arrays.copyOf(buf, p);
	}
	
	private char[][] nm(int n, int m)
	{
		char[][] map = new char[n][];
		for(int i = 0;i < n;i++)map[i] = ns(m);
		return map;
	}
	
	private int[] na(int n)
	{
		int[] a = new int[n];
		for(int i = 0;i < n;i++)a[i] = ni();
		return a;
	}
	
	private int ni()
	{
		int num = 0, b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	
	private long nl()
	{
		long num = 0;
		int b;
		boolean minus = false;
		while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));
		if(b == '-'){
			minus = true;
			b = readByte();
		}
		
		while(true){
			if(b >= '0' && b <= '9'){
				num = num * 10 + (b - '0');
			}else{
				return minus ? -num : num;
			}
			b = readByte();
		}
	}
	
	private static void tr(Object... o) { System.out.println(Arrays.deepToString(o)); }
}