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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 29 |
| 5 | 70 |
| 6 | 169 |
| 7 | 410 |
| 8 | 1005 |
| 9 | 2500 |
| 10 | 6325 |
| 11 | 16276 |
| 12 | 42549 |
| 13 | 112832 |
| 14 | 303073 |
| 15 | 823442 |
| 16 | 2259917 |
| 17 | 6256610 |
| 18 | 17451117 |
| 19 | 48984114 |
| 20 | 138233969 |
| 21 | 391876318 |
| 22 | 1115233413 |
| 23 | 3184379758 |
| 24 | 9118632645 |
| 25 | 26176992668 |
| 26 | 75311867001 |
| 27 | 217096296680 |
| 28 | 626898050125 |
[1,2,5,12,29,70,169,410,1005,2500,6325,16276, 42549,112832,303073,823442,2259917,6256610, 17451117,48984114,138233969,391876318,1115233413, 3184379758,9118632645,26176992668,75311867001, 217096296680,626898050125] |