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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 17 |
| 5 | 20 |
| 6 | 117 |
| 7 | 254 |
| 8 | 371 |
| 9 | 1367 |
| 10 | 15408 |
| 11 | 47591 |
| 12 | 62999 |
| 13 | 299587 |
| 14 | 2759282 |
| 15 | 3058869 |
| 16 | 21112496 |
| 17 | 24171365 |
| 18 | 93626591 |
| 19 | 305051138 |
| 20 | 398677729 |
| 21 | 1899762054 |
| 22 | 4198201837 |
| 23 | 6097963891 |
| 24 | 10296165728 |
| 25 | 36986461075 |
| 26 | 47282626803 |
| 27 | 178834341484 |
| 28 | 762619992739 |
| 29 | 941454334223 |
[1,2,3,17,20,117,254,371,1367,15408,47591,62999, 299587,2759282,3058869,21112496,24171365,93626591, 305051138,398677729,1899762054,4198201837, 6097963891,10296165728,36986461075,47282626803, 178834341484,762619992739,941454334223] |