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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 12 |
| 4 | 38 |
| 5 | 88 |
| 6 | 281 |
| 7 | 742 |
| 8 | 2273 |
| 9 | 6607 |
| 10 | 19889 |
| 11 | 59078 |
| 12 | 177823 |
| 13 | 531478 |
| 14 | 1595861 |
| 15 | 4783318 |
| 16 | 14353514 |
| 17 | 43046774 |
| 18 | 129154229 |
| 19 | 387420550 |
| 20 | 1162301563 |
| 21 | 3486786776 |
| 22 | 10460471461 |
| 23 | 31381059688 |
| 24 | 94143541523 |
| 25 | 282429537137 |
| 26 | 847289672533 |
| 27 | 2541865848284 |
| 28 | 7625600677855 |
[1,5,12,38,88,281,742,2273,6607,19889,59078, 177823,531478,1595861,4783318,14353514,43046774, 129154229,387420550,1162301563,3486786776, 10460471461,31381059688,94143541523,282429537137, 847289672533,2541865848284,7625600677855] |