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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 22 |
| 4 | 60 |
| 5 | 163 |
| 6 | 443 |
| 7 | 1204 |
| 8 | 3273 |
| 9 | 8897 |
| 10 | 24185 |
| 11 | 65742 |
| 12 | 178705 |
| 13 | 485771 |
| 14 | 1320462 |
| 15 | 3589388 |
| 16 | 9756968 |
| 17 | 26522189 |
| 18 | 72094784 |
| 19 | 195973941 |
| 20 | 532712403 |
| 21 | 1448062445 |
| 22 | 3936241831 |
| 23 | 10699814642 |
| 24 | 29085111709 |
| 25 | 79061530637 |
| 26 | 214911522061 |
| 27 | 584190085145 |
[1,3,8,22,60,163,443,1204,3273,8897,24185,65742, 178705,485771,1320462,3589388,9756968,26522189, 72094784,195973941,532712403,1448062445, 3936241831,10699814642,29085111709,79061530637, 214911522061,584190085145] |