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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 73 |
| 3 | 1417 |
| 4 | 19834 |
| 5 | 190131 |
| 6 | 1398547 |
| 7 | 8246011 |
| 8 | 40837569 |
| 9 | 174901563 |
| 10 | 664006236 |
| 11 | 2274999093 |
| 12 | 7139338769 |
| 13 | 20758868781 |
| 14 | 56466073587 |
| 15 | 144806582536 |
| 16 | 352420554194 |
| 17 | 818441723112 |
| 18 | 1822255658908 |
| 19 | 3905392549491 |
| 20 | 8084697432576 |
| 21 | 16214886608495 |
| 22 | 31590986308810 |
| 23 | 59926495673780 |
[1,1,73,1417,19834,190131,1398547,8246011, 40837569,174901563,664006236,2274999093, 7139338769,20758868781,56466073587,144806582536, 352420554194,818441723112,1822255658908, 3905392549491,8084697432576,16214886608495, 31590986308810,59926495673780] |