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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 149 |
| 5 | 562 |
| 6 | 2066 |
| 7 | 7474 |
| 8 | 26737 |
| 9 | 94900 |
| 10 | 334909 |
| 11 | 1176842 |
| 12 | 4121632 |
| 13 | 14397370 |
| 14 | 50185498 |
| 15 | 174628420 |
| 16 | 606755258 |
| 17 | 2105552976 |
| 18 | 7298685677 |
| 19 | 25275876584 |
| 20 | 87457546835 |
| 21 | 302382185770 |
| 22 | 1044756677132 |
| 23 | 3607460520006 |
| 24 | 12449135054480 |
[2,9,38,149,562,2066,7474,26737,94900,334909, 1176842,4121632,14397370,50185498,174628420, 606755258,2105552976,7298685677,25275876584, 87457546835,302382185770,1044756677132, 3607460520006,12449135054480] |