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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 22 |
| 4 | 63 |
| 5 | 185 |
| 6 | 550 |
| 7 | 1644 |
| 8 | 4925 |
| 9 | 14767 |
| 10 | 44292 |
| 11 | 132866 |
| 12 | 398587 |
| 13 | 1195749 |
| 14 | 3587234 |
| 15 | 10761688 |
| 16 | 32285049 |
| 17 | 96855131 |
| 18 | 290565376 |
| 19 | 871696110 |
| 20 | 2615088311 |
| 21 | 7845264913 |
| 22 | 23535794718 |
| 23 | 70607384132 |
| 24 | 211822152373 |
| 25 | 635466457095 |
| 26 | 1906399371260 |
[1,3,8,22,63,185,550,1644,4925,14767,44292,132866, 398587,1195749,3587234,10761688,32285049,96855131, 290565376,871696110,2615088311,7845264913, 23535794718,70607384132,211822152373,635466457095, 1906399371260] |