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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 22 |
| 5 | 63 |
| 6 | 191 |
| 7 | 573 |
| 8 | 1752 |
| 9 | 5372 |
| 10 | 16597 |
| 11 | 51465 |
| 12 | 160258 |
| 13 | 500551 |
| 14 | 1567881 |
| 15 | 4922687 |
| 16 | 15488481 |
| 17 | 48821964 |
| 18 | 154147654 |
| 19 | 487412324 |
| 20 | 1543231353 |
| 21 | 4891986889 |
| 22 | 15524303265 |
| 23 | 49314008259 |
| 24 | 156791992914 |
| 25 | 498931763064 |
| 26 | 1588891019625 |
[1,1,3,7,22,63,191,573,1752,5372,16597,51465, 160258,500551,1567881,4922687,15488481,48821964, 154147654,487412324,1543231353,4891986889, 15524303265,49314008259,156791992914,498931763064, 1588891019625] |