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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 81 |
| 3 | 525 |
| 4 | 3105 |
| 5 | 18939 |
| 6 | 114381 |
| 7 | 693129 |
| 8 | 4195557 |
| 9 | 25405586 |
| 10 | 153820395 |
| 11 | 931359050 |
| 12 | 5639156409 |
| 13 | 34143908573 |
| 14 | 206733865761 |
| 15 | 1251728824798 |
| 16 | 7578945799704 |
| 17 | 45888871327435 |
| 18 | 277847147039527 |
| 19 | 1682304127857000 |
| 20 | 10185986079451152 |
| 21 | 61673933253012813 |
| 22 | 373422269794761171 |
| 23 | 2260990733622821388 |
[9,81,525,3105,18939,114381,693129,4195557, 25405586,153820395,931359050,5639156409, 34143908573,206733865761,1251728824798, 7578945799704,45888871327435,277847147039527, 1682304127857000,10185986079451152, 61673933253012813,373422269794761171, 2260990733622821388] |