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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 62 |
| 4 | 394 |
| 5 | 2562 |
| 6 | 16966 |
| 7 | 113794 |
| 8 | 770458 |
| 9 | 5254658 |
| 10 | 36046470 |
| 11 | 248449104 |
| 12 | 1719175846 |
| 13 | 11935608518 |
| 14 | 83100064834 |
| 15 | 579994824042 |
| 16 | 4056746450106 |
| 17 | 28428354905268 |
| 18 | 199550820571858 |
| 19 | 1402832286126650 |
| 20 | 9875127071717694 |
| 21 | 69599814539512900 |
| 22 | 491081313666879968 |
| 23 | 3468458841769675496 |
[1,2,10,62,394,2562,16966,113794,770458,5254658, 36046470,248449104,1719175846,11935608518, 83100064834,579994824042,4056746450106, 28428354905268,199550820571858,1402832286126650, 9875127071717694,69599814539512900, 491081313666879968,3468458841769675496] |