C++ :

#include<iostream>
#include<iomanip>
using namespace std;

int main()
{
	int n;
	cin>>n;int a[21][21];
	for (int i=n,k=1; i>=1; i--)
		for (int j=1,x=i; x<=n; j++) a[x++][j]=k++;
	for (int i=1; i<=n; i++)
	{
		for (int j=1; j<=i; j++) cout<<setw(4)<<a[i][j];
		cout<<endl;
	}
	return 0;
}