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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 14 |
| 2 | 105 |
| 3 | 574 |
| 4 | 2576 |
| 5 | 10052 |
| 6 | 35273 |
| 7 | 113794 |
| 8 | 342699 |
| 9 | 974176 |
| 10 | 2635955 |
| 11 | 6833540 |
| 12 | 17061345 |
| 13 | 41197422 |
| 14 | 96544003 |
| 15 | 220212384 |
| 16 | 490104727 |
| 17 | 1066552228 |
| 18 | 2273590095 |
| 19 | 4755188704 |
| 20 | 9771319068 |
| 21 | 19751596934 |
| 22 | 39317784863 |
| 23 | 77150246040 |
| 24 | 149357609184 |
| 25 | 285497384004 |
| 26 | 539227765104 |
| 27 | 1006978117880 |
[1,14,105,574,2576,10052,35273,113794,342699, 974176,2635955,6833540,17061345,41197422,96544003, 220212384,490104727,1066552228,2273590095, 4755188704,9771319068,19751596934,39317784863, 77150246040,149357609184,285497384004, 539227765104,1006978117880] |