The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 72 |
| 3 | 576 |
| 4 | 4608 |
| 5 | 36864 |
| 6 | 294912 |
| 7 | 2359296 |
| 8 | 18874368 |
| 9 | 150994944 |
| 10 | 1207959552 |
| 11 | 9663676380 |
| 12 | 77309410752 |
| 13 | 618475283748 |
| 14 | 4947802251840 |
| 15 | 39582417869568 |
| 16 | 316659341795328 |
| 17 | 2533274725072896 |
| 18 | 20266197726265344 |
| 19 | 162129581215580160 |
[1,9,72,576,4608,36864,294912,2359296,18874368, 150994944,1207959552,9663676380,77309410752, 618475283748,4947802251840,39582417869568, 316659341795328,2533274725072896, 20266197726265344,162129581215580160] |