C++ :

# include <iostream>
using namespace std;
char a[30] = "0123456789ABCDEFGHIJKLMN";
int main(){
    int n;
    cin >> n;
    for (int i = 1; i <= n; i ++){
        for (int j = 1; j <= n - i; j ++){
            cout << " ";
        }
        for (int j = 1; j <= i; j ++){
            cout << a[j];
        }
        for (int j = i - 1; j >= 1; j --){
            cout << a[j];
        }
        cout << endl;
    }
    return 0;
}

Pascal :

var
 n,i,j,b,x,m:integer;
 begin
 readln(n);
 for i:=1 to n do
   begin
   for j:=1 to i do
     begin
      if j>9 then x:=55+j else x:=48+j;
      b:=n-i+1;
      if j=1 then write(chr(x):b)
      else write(chr(x));
     end;
   for m:=i-1 downto 1 do
   begin
   if m>9 then x:=55+m else x:=48+m;
     write(chr(x));
   end;
   writeln; 
   end;
   end.