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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 83 |
| 6 | 281 |
| 7 | 971 |
| 8 | 3417 |
| 9 | 12264 |
| 10 | 44438 |
| 11 | 162904 |
| 12 | 602266 |
| 13 | 2241764 |
| 14 | 8400548 |
| 15 | 31634918 |
| 16 | 119702435 |
| 17 | 454780012 |
| 18 | 1733848968 |
| 19 | 6631814922 |
| 20 | 25436402695 |
| 21 | 97810174385 |
| 22 | 376967520192 |
| 23 | 1455826275320 |
| 24 | 5632909116247 |
| 25 | 21831857984083 |
| 26 | 84746834213967 |
| 27 | 329439820828496 |
| 28 | 1282316672529298 |
| 29 | 4997344941893617 |
[1,1,3,8,26,83,281,971,3417,12264,44438,162904, 602266,2241764,8400548,31634918,119702435, 454780012,1733848968,6631814922,25436402695, 97810174385,376967520192,1455826275320, 5632909116247,21831857984083,84746834213967, 329439820828496,1282316672529298,4997344941893617] |