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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 1 |
| 3 | 10 |
| 4 | 17 |
| 5 | 56 |
| 6 | 255 |
| 7 | 1038 |
| 8 | 4771 |
| 9 | 21866 |
| 10 | 102060 |
| 11 | 476499 |
| 12 | 2227609 |
| 13 | 10440370 |
| 14 | 48996354 |
| 15 | 230159202 |
| 16 | 1081764728 |
| 17 | 5086004704 |
| 18 | 23916740145 |
| 19 | 112479869517 |
| 20 | 529026120838 |
| 21 | 2488273643127 |
| 22 | 11703911410284 |
| 23 | 55051772837784 |
[8,1,10,17,56,255,1038,4771,21866,102060,476499, 2227609,10440370,48996354,230159202,1081764728, 5086004704,23916740145,112479869517,529026120838, 2488273643127,11703911410284,55051772837784] |