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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 5 |
| 5 | 21 |
| 6 | 101 |
| 7 | 581 |
| 8 | 3605 |
| 9 | 29141 |
| 10 | 239701 |
| 11 | 2205861 |
| 12 | 22832005 |
| 13 | 246573061 |
| 14 | 2990463301 |
| 15 | 38108222341 |
| 16 | 518783617205 |
| 17 | 7633121129781 |
| 18 | 116869543894901 |
| 19 | 1918479435194021 |
| 20 | 33025793008567205 |
| 21 | 595507639576003301 |
| 22 | 11356021765206934501 |
| 23 | 224730968057626784901 |
| 24 | 4667903267042610866005 |
| 25 | 101036430792914926153621 |
| 26 | 2269220040134583532958101 |
[1,1,1,1,5,21,101,581,3605,29141,239701,2205861, 22832005,246573061,2990463301,38108222341, 518783617205,7633121129781,116869543894901, 1918479435194021,33025793008567205, 595507639576003301,11356021765206934501, 224730968057626784901,4667903267042610866005, 101036430792914926153621, 2269220040134583532958101] |