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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
| 6 | 726 |
| 7 | 5047 |
| 8 | 20168 |
| 9 | 60489 |
| 10 | 151210 |
| 11 | 332651 |
| 12 | 665292 |
| 13 | 1235533 |
| 14 | 2162174 |
| 15 | 3603615 |
| 16 | 5765776 |
| 17 | 8910737 |
| 18 | 13366098 |
| 19 | 19535059 |
| 20 | 27907220 |
| 21 | 39070101 |
| 22 | 53721382 |
| 23 | 72681863 |
| 24 | 96909144 |
| 25 | 127512025 |
| 26 | 165765626 |
| 27 | 213127227 |
| 28 | 271252828 |
| 29 | 342014429 |
[0,1,2,3,4,5,726,5047,20168,60489,151210,332651, 665292,1235533,2162174,3603615,5765776,8910737, 13366098,19535059,27907220,39070101,53721382, 72681863,96909144,127512025,165765626,213127227, 271252828,342014429] |