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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 23 |
| 4 | 117 |
| 5 | 140 |
| 6 | 537 |
| 7 | 9269 |
| 8 | 28344 |
| 9 | 37613 |
| 10 | 216409 |
| 11 | 2418112 |
| 12 | 2634521 |
| 13 | 5052633 |
| 14 | 174424043 |
| 15 | 179476676 |
| 16 | 353900719 |
| 17 | 4072384585 |
| 18 | 20715823644 |
| 19 | 24788208229 |
| 20 | 95080448331 |
| 21 | 1641155829856 |
| 22 | 5018547937899 |
| 23 | 6659703767755 |
| 24 | 38317066776674 |
| 25 | 428147438311169 |
[1,1,2,23,117,140,537,9269,28344,37613,216409, 2418112,2634521,5052633,174424043,179476676, 353900719,4072384585,20715823644,24788208229, 95080448331,1641155829856,5018547937899, 6659703767755,38317066776674,428147438311169] |