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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 29 |
| 5 | 71 |
| 6 | 336 |
| 7 | 932 |
| 8 | 4593 |
| 9 | 13690 |
| 10 | 69708 |
| 11 | 222718 |
| 12 | 1163734 |
| 13 | 3902016 |
| 14 | 20825927 |
| 15 | 73229397 |
| 16 | 397806717 |
| 17 | 1452193925 |
| 18 | 8016518379 |
| 19 | 30328368519 |
| 20 | 169781766056 |
| 21 | 662143701506 |
| 22 | 3755514158949 |
| 23 | 15071604241851 |
| 24 | 86496856963200 |
| 25 | 356063096545571 |
| 26 | 2066351471542036 |
[1,1,3,7,29,71,336,932,4593,13690,69708,222718, 1163734,3902016,20825927,73229397,397806717, 1452193925,8016518379,30328368519,169781766056, 662143701506,3755514158949,15071604241851, 86496856963200,356063096545571,2066351471542036] |