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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 59 |
| 4 | 432 |
| 5 | 3161 |
| 6 | 23128 |
| 7 | 169219 |
| 8 | 1238112 |
| 9 | 9058801 |
| 10 | 66279848 |
| 11 | 484944779 |
| 12 | 3548158992 |
| 13 | 25960548041 |
| 14 | 189943589368 |
| 15 | 1389745974739 |
| 16 | 10168249851072 |
| 17 | 74397268934881 |
| 18 | 544336902223688 |
| 19 | 3982708873115099 |
| 20 | 29139986473802352 |
| 21 | 213206347424843321 |
| 22 | 1559950847029734808 |
[0,1,8,59,432,3161,23128,169219,1238112,9058801, 66279848,484944779,3548158992,25960548041, 189943589368,1389745974739,10168249851072, 74397268934881,544336902223688,3982708873115099, 29139986473802352,213206347424843321, 1559950847029734808] |