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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 24 |
| 3 | 40 |
| 4 | 246 |
| 5 | 899 |
| 6 | 4262 |
| 7 | 18773 |
| 8 | 86217 |
| 9 | 393045 |
| 10 | 1797614 |
| 11 | 8250018 |
| 12 | 37806949 |
| 13 | 173560449 |
| 14 | 796357535 |
| 15 | 3655798608 |
| 16 | 16780585631 |
| 17 | 77034933529 |
| 18 | 353640484316 |
| 19 | 1623486194095 |
| 20 | 7453088205576 |
| 21 | 34215785172369 |
| 22 | 157078858232301 |
[1,24,40,246,899,4262,18773,86217,393045,1797614, 8250018,37806949,173560449,796357535,3655798608, 16780585631,77034933529,353640484316, 1623486194095,7453088205576,34215785172369, 157078858232301] |