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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 29 |
| 5 | 97 |
| 6 | 337 |
| 7 | 1200 |
| 8 | 4352 |
| 9 | 15964 |
| 10 | 59163 |
| 11 | 221154 |
| 12 | 832740 |
| 13 | 3153898 |
| 14 | 12001752 |
| 15 | 45860585 |
| 16 | 175873274 |
| 17 | 676595506 |
| 18 | 2610061582 |
| 19 | 10092824792 |
| 20 | 39110984254 |
| 21 | 151848868126 |
| 22 | 590564253255 |
| 23 | 2300328671191 |
| 24 | 8972524560949 |
| 25 | 35041779245101 |
| 26 | 137011117055180 |
| 27 | 536266828836428 |
| 28 | 2100987903534724 |
[1,1,3,9,29,97,337,1200,4352,15964,59163,221154, 832740,3153898,12001752,45860585,175873274, 676595506,2610061582,10092824792,39110984254, 151848868126,590564253255,2300328671191, 8972524560949,35041779245101,137011117055180, 536266828836428,2100987903534724] |