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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 4 |
| 5 | 5 |
| 6 | 12 |
| 7 | 19 |
| 8 | 46 |
| 9 | 95 |
| 10 | 230 |
| 11 | 528 |
| 12 | 1320 |
| 13 | 3219 |
| 14 | 8172 |
| 15 | 20714 |
| 16 | 53478 |
| 17 | 138635 |
| 18 | 363486 |
| 19 | 957858 |
| 20 | 2543476 |
| 21 | 6788019 |
| 22 | 18218772 |
| 23 | 49120019 |
| 24 | 133036406 |
| 25 | 361736109 |
| 26 | 987316658 |
| 27 | 2703991820 |
| 28 | 7429445752 |
| 29 | 20473889133 |
| 30 | 56579632732 |
| 31 | 156766505691 |
[1,1,2,2,4,5,12,19,46,95,230,528,1320,3219,8172, 20714,53478,138635,363486,957858,2543476,6788019, 18218772,49120019,133036406,361736109,987316658, 2703991820,7429445752,20473889133,56579632732, 156766505691] |