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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 49 |
| 3 | 262 |
| 4 | 1286 |
| 5 | 5944 |
| 6 | 26262 |
| 7 | 111996 |
| 8 | 464103 |
| 9 | 1877904 |
| 10 | 7446735 |
| 11 | 29021490 |
| 12 | 111405780 |
| 13 | 422003520 |
| 14 | 1579757580 |
| 15 | 5851519704 |
| 16 | 21468622077 |
| 17 | 78087814776 |
| 18 | 281798184573 |
| 19 | 1009617794334 |
| 20 | 3593281988754 |
| 21 | 12710491403112 |
| 22 | 44705999907666 |
[1,8,49,262,1286,5944,26262,111996,464103,1877904, 7446735,29021490,111405780,422003520,1579757580, 5851519704,21468622077,78087814776,281798184573, 1009617794334,3593281988754,12710491403112, 44705999907666] |