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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 65 |
| 5 | 354 |
| 6 | 2035 |
| 7 | 12151 |
| 8 | 74618 |
| 9 | 468233 |
| 10 | 2989093 |
| 11 | 19350384 |
| 12 | 126730636 |
| 13 | 838161358 |
| 14 | 5589998777 |
| 15 | 37552863737 |
| 16 | 253877488505 |
| 17 | 1725951649616 |
| 18 | 11791929640102 |
| 19 | 80921655496164 |
| 20 | 557538161292336 |
| 21 | 3855215134210479 |
| 22 | 26745074320086283 |
| 23 | 186095529221819237 |
| 24 | 1298423607303399905 |
[1,3,13,65,354,2035,12151,74618,468233,2989093, 19350384,126730636,838161358,5589998777, 37552863737,253877488505,1725951649616, 11791929640102,80921655496164,557538161292336, 3855215134210479,26745074320086283, 186095529221819237,1298423607303399905] |