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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 35 |
| 6 | 94 |
| 7 | 254 |
| 8 | 688 |
| 9 | 1872 |
| 10 | 5115 |
| 11 | 14038 |
| 12 | 38689 |
| 13 | 107055 |
| 14 | 297336 |
| 15 | 828699 |
| 16 | 2317098 |
| 17 | 6498114 |
| 18 | 18273861 |
| 19 | 51521238 |
| 20 | 145604868 |
| 21 | 412407942 |
| 22 | 1170507375 |
| 23 | 3328570513 |
| 24 | 9482518041 |
| 25 | 27059673745 |
| 26 | 77340925350 |
| 27 | 221382318131 |
| 28 | 634578781229 |
| 29 | 1821388557507 |
[1,1,2,5,13,35,94,254,688,1872,5115,14038,38689, 107055,297336,828699,2317098,6498114,18273861, 51521238,145604868,412407942,1170507375, 3328570513,9482518041,27059673745,77340925350, 221382318131,634578781229,1821388557507] |