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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 14 |
| 6 | 42 |
| 7 | 79 |
| 8 | 254 |
| 9 | 506 |
| 10 | 1702 |
| 11 | 3548 |
| 12 | 12320 |
| 13 | 26666 |
| 14 | 94794 |
| 15 | 211751 |
| 16 | 766362 |
| 17 | 1758352 |
| 18 | 6453812 |
| 19 | 15150922 |
| 20 | 56238710 |
| 21 | 134659120 |
[1,1,2,3,8,14,42,79,254,506,1702,3548,12320,26666, 94794,211751,766362,1758352,6453812,15150922, 56238710,134659120] |