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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 36 |
| 4 | 169 |
| 5 | 749 |
| 6 | 3620 |
| 7 | 16829 |
| 8 | 82399 |
| 9 | 391822 |
| 10 | 1932376 |
| 11 | 9315468 |
| 12 | 46137134 |
| 13 | 224369868 |
| 14 | 1114224182 |
| 15 | 5451178811 |
| 16 | 27118628625 |
| 17 | 133243991331 |
| 18 | 663673232831 |
| 19 | 3271244384521 |
| 20 | 16307808997278 |
| 21 | 80575657441894 |
| 22 | 401939334649959 |
| 23 | 1989692637495554 |
| 24 | 9929943962723711 |
| 25 | 49228973551576867 |
| 26 | 245774352819824880 |
[1,2,9,36,169,749,3620,16829,82399,391822,1932376, 9315468,46137134,224369868,1114224182,5451178811, 27118628625,133243991331,663673232831, 3271244384521,16307808997278,80575657441894, 401939334649959,1989692637495554,9929943962723711, 49228973551576867,245774352819824880] |