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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 29 |
| 4 | 96 |
| 5 | 324 |
| 6 | 1111 |
| 7 | 3861 |
| 8 | 13572 |
| 9 | 48178 |
| 10 | 172482 |
| 11 | 622098 |
| 12 | 2258416 |
| 13 | 8246190 |
| 14 | 30264435 |
| 15 | 111585765 |
| 16 | 413126460 |
| 17 | 1535267250 |
| 18 | 5724840990 |
| 19 | 21413721510 |
| 20 | 80326153440 |
| 21 | 302105210160 |
| 22 | 1138957917318 |
| 23 | 4303550907234 |
| 24 | 16294686579016 |
[1,3,9,29,96,324,1111,3861,13572,48178,172482, 622098,2258416,8246190,30264435,111585765, 413126460,1535267250,5724840990,21413721510, 80326153440,302105210160,1138957917318, 4303550907234,16294686579016] |