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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 29 |
| 5 | 88 |
| 6 | 268 |
| 7 | 813 |
| 8 | 2469 |
| 9 | 7499 |
| 10 | 22774 |
| 11 | 69165 |
| 12 | 210056 |
| 13 | 637944 |
| 14 | 1937449 |
| 15 | 5884073 |
| 16 | 17870051 |
| 17 | 54271714 |
| 18 | 164824317 |
| 19 | 500574856 |
| 20 | 1520256180 |
| 21 | 4617049429 |
| 22 | 14022074509 |
| 23 | 42585329995 |
| 24 | 129332527054 |
| 25 | 392785556813 |
| 26 | 1192897851416 |
[1,1,3,10,29,88,268,813,2469,7499,22774,69165, 210056,637944,1937449,5884073,17870051,54271714, 164824317,500574856,1520256180,4617049429, 14022074509,42585329995,129332527054,392785556813, 1192897851416] |