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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 15 |
| 4 | 44 |
| 5 | 125 |
| 6 | 370 |
| 7 | 1099 |
| 8 | 3288 |
| 9 | 9849 |
| 10 | 29534 |
| 11 | 88583 |
| 12 | 265732 |
| 13 | 797173 |
| 14 | 2391498 |
| 15 | 7174467 |
| 16 | 21523376 |
| 17 | 64570097 |
| 18 | 193710262 |
| 19 | 581130751 |
| 20 | 1743392220 |
| 21 | 5230176621 |
| 22 | 15690529826 |
| 23 | 47071589435 |
| 24 | 141214768264 |
| 25 | 423644304745 |
| 26 | 1270932914190 |
| 27 | 3812798742519 |
| 28 | 11438396227508 |
| 29 | 34315188682469 |
| 30 | 102945566047354 |
[1,6,15,44,125,370,1099,3288,9849,29534,88583, 265732,797173,2391498,7174467,21523376,64570097, 193710262,581130751,1743392220,5230176621, 15690529826,47071589435,141214768264,423644304745, 1270932914190,3812798742519,11438396227508, 34315188682469,102945566047354] |