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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 38 |
| 4 | 133 |
| 5 | 468 |
| 6 | 1660 |
| 7 | 5932 |
| 8 | 21346 |
| 9 | 77301 |
| 10 | 281545 |
| 11 | 1030778 |
| 12 | 3791597 |
| 13 | 14006456 |
| 14 | 51941576 |
| 15 | 193301120 |
| 16 | 721697246 |
| 17 | 2702472854 |
| 18 | 10147300982 |
| 19 | 38197179692 |
| 20 | 144119279906 |
| 21 | 544941540968 |
| 22 | 2064663329656 |
| 23 | 7837201508508 |
| 24 | 29801069731228 |
| 25 | 113504582390857 |
| 26 | 432973857932389 |
[1,3,11,38,133,468,1660,5932,21346,77301,281545, 1030778,3791597,14006456,51941576,193301120, 721697246,2702472854,10147300982,38197179692, 144119279906,544941540968,2064663329656, 7837201508508,29801069731228,113504582390857, 432973857932389] |