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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 38 |
| 3 | 140 |
| 4 | 443 |
| 5 | 1268 |
| 6 | 3384 |
| 7 | 8584 |
| 8 | 20965 |
| 9 | 49744 |
| 10 | 115402 |
| 11 | 262996 |
| 12 | 590831 |
| 13 | 1311900 |
| 14 | 2884956 |
| 15 | 6293040 |
| 16 | 13633305 |
| 17 | 29362200 |
| 18 | 62916910 |
| 19 | 134220380 |
| 20 | 285215651 |
| 21 | 603983108 |
| 22 | 1275072128 |
| 23 | 2684358680 |
| 24 | 5637149133 |
| 25 | 11811165088 |
[1,8,38,140,443,1268,3384,8584,20965,49744,115402, 262996,590831,1311900,2884956,6293040,13633305, 29362200,62916910,134220380,285215651,603983108, 1275072128,2684358680,5637149133,11811165088] |