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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 23 |
| 4 | 85 |
| 5 | 340 |
| 6 | 1517 |
| 7 | 7489 |
| 8 | 41276 |
| 9 | 252410 |
| 10 | 1706071 |
| 11 | 12660012 |
| 12 | 102447112 |
| 13 | 898081422 |
| 14 | 8477941776 |
| 15 | 85729296020 |
| 16 | 924345402273 |
| 17 | 10584325318278 |
| 18 | 128259347448244 |
| 19 | 1639694094741643 |
| 20 | 22053783907891362 |
| 21 | 311294619360437722 |
| 22 | 4601020643330758040 |
| 23 | 71063337073204684379 |
| 24 | 1144820435086864897289 |
[1,2,7,23,85,340,1517,7489,41276,252410,1706071, 12660012,102447112,898081422,8477941776, 85729296020,924345402273,10584325318278, 128259347448244,1639694094741643, 22053783907891362,311294619360437722, 4601020643330758040,71063337073204684379, 1144820435086864897289] |