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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 12 |
| 5 | 45 |
| 6 | 222 |
| 7 | 1239 |
| 8 | 7672 |
| 9 | 54873 |
| 10 | 416410 |
| 11 | 3577739 |
| 12 | 32324292 |
| 13 | 322495173 |
| 14 | 3382216502 |
| 15 | 38370542175 |
| 16 | 457713511280 |
| 17 | 5817952885169 |
| 18 | 77686268202162 |
| 19 | 1093812528874387 |
| 20 | 16145162631579900 |
| 21 | 249472828725529437 |
| 22 | 4030053480328871182 |
| 23 | 67807763939709678951 |
[0,1,2,3,12,45,222,1239,7672,54873,416410,3577739, 32324292,322495173,3382216502,38370542175, 457713511280,5817952885169,77686268202162, 1093812528874387,16145162631579900, 249472828725529437,4030053480328871182, 67807763939709678951] |