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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 16 |
| 6 | 62 |
| 7 | 230 |
| 8 | 1114 |
| 9 | 5268 |
| 10 | 30702 |
| 11 | 176226 |
| 12 | 1201638 |
| 13 | 8107464 |
| 14 | 63339702 |
| 15 | 491010102 |
| 16 | 4324845834 |
| 17 | 37867131900 |
| 18 | 371275954758 |
| 19 | 3623124865986 |
| 20 | 39137296073094 |
| 21 | 421150512316032 |
| 22 | 4969568447400366 |
| 23 | 58455531552960198 |
[1,1,2,6,16,62,230,1114,5268,30702,176226,1201638, 8107464,63339702,491010102,4324845834,37867131900, 371275954758,3623124865986,39137296073094, 421150512316032,4969568447400366, 58455531552960198] |