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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 51 |
| 4 | 205 |
| 5 | 820 |
| 6 | 3277 |
| 7 | 13107 |
| 8 | 52428 |
| 9 | 209715 |
| 10 | 838861 |
| 11 | 3355444 |
| 12 | 13421773 |
| 13 | 53687091 |
| 14 | 214748364 |
| 15 | 858993459 |
| 16 | 3435973837 |
| 17 | 13743895348 |
| 18 | 54975581389 |
| 19 | 219902325555 |
| 20 | 879609302220 |
| 21 | 3518437208883 |
| 22 | 14073748835533 |
| 23 | 56294995342132 |
| 24 | 225179981368525 |
| 25 | 900719925474099 |
[1,3,12,51,205,820,3277,13107,52428,209715,838861, 3355444,13421773,53687091,214748364,858993459, 3435973837,13743895348,54975581389,219902325555, 879609302220,3518437208883,14073748835533, 56294995342132,225179981368525,900719925474099] |