C++ Inverse number pyramid - c++

Question

Okay so i'm trying to make a code that will read in a positive odd integer and output an inverse pyramid starting with that number and descending to 1 and cutting off the first and last digit in the next line and so on. So if i entered 7 it would display:
7654321
65432
543
4
The i 'th row contains n-(2i-2) but I'm not sure how to use that.
Thanks for your help.
This is what I have so far:
#include <iostream>
using namespace std;
int main()
{
int n,i,j;
cout << "Enter a positive odd number: " << endl;
cin >> n ;
i=n;
while(n%2 ==0)
{
cout<< "Invalid number." << endl;
cout<< "Enter a positive odd number: " << endl;
cin >> n ;
}
for(i=n; i<=n && i>0 ; i--)
{
for(j=i; j<=i; j--)
{
cout<< i%10 ;
}
cout<<endl;
}
return(0);
}

Answer 1

Number the character positions on screen like this:
+----+----+----+----+----+----+----+
| 0 0| 0 1| 0 2| 0 3| 0 4| 0 5| 0 6|
+----+----+----+----+----+----+----+
| 1 0| 1 1| 1 2| 1 3| 1 4| 1 5| 1 6|
+----+----+----+----+----+----+----+
| 2 0| 2 1| 2 2| 2 3| 2 4| 2 5| 2 6|
+----+----+----+----+----+----+----+
| 3 0| 3 1| 3 2| 3 3| 3 4| 3 5| 3 6|
+----+----+----+----+----+----+----+
and check what goes in there
+----+----+----+----+----+----+----+
| 7 | 6 | 5 | 4 | 3 | 2 | 1 |
+----+----+----+----+----+----+----+
| | 6 | 5 | 4 | 3 | 2 | |
+----+----+----+----+----+----+----+
| | | 5 | 4 | 3 | | |
+----+----+----+----+----+----+----+
| | | | 4 | | | |
+----+----+----+----+----+----+----+
Now find the relation between x, y, the value to print, and the initial number.