A015123 as a triangular array
| | | | | | | | | 1 |
| | | | | | | | | 1 | | 1 |
| | | | | | | | 1 | | -9 | | 1 |
| | | | | | | 1 | | 91 | | 91 | | 1 |
| | | | | | 1 | | -909 | | 9191 | | -909 | | 1 |
| | | | | 1 | | 9091 | | 918191 | | 918191 | | 9091 | | 1 |
| | | | 1 | | -90909 | | 91828191 | | -917272809 | | 91828191 | | -90909 | | 1 |
| | | 1 | | 909091 | | 9182728191 | | 917364637191 | | 917364637191 | | 9182728191 | | 909091 | | 1 |
| | 1 | | -9090909 | | 918273728191 |
|
A015123 as a square array
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1
| | 1 | -9 | 91 | -909 | 9091 | -90909 | 909091 | -9090909
| | 1 | 91 | 9191 | 918191 | 91828191 | 9182728191 | 918273728191
| | 1 | -909 | 918191 | -917272809 | 917364637191
| | 1 | 9091 | 91828191 | 917364637191
| | 1 | -90909 | 9182728191
| | 1 | 909091
| | 1
|
A015123 as an upper right triangle
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1
| | 1 | -9 | 91 | -909 | 9091 | -90909 | 909091 | -9090909
| | | 1 | 91 | 9191 | 918191 | 91828191 | 9182728191 | 918273728191
| | | | 1 | -909 | 918191 | -917272809 | 917364637191
| | | | | 1 | 9091 | 91828191 | 917364637191
| | | | | | 1 | -90909 | 9182728191
| | | | | | | 1 | 909091
| | | | | | | | 1
| | | | | | | |
|
|
