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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 30 |
| 4 | 108 |
| 5 | 357 |
| 6 | 1205 |
| 7 | 3838 |
| 8 | 12083 |
| 9 | 36896 |
| 10 | 110828 |
| 11 | 326281 |
| 12 | 946086 |
| 13 | 2700026 |
| 14 | 7602642 |
| 15 | 21128513 |
| 16 | 58028309 |
| 17 | 157588912 |
| 18 | 423534324 |
| 19 | 1127102360 |
| 20 | 2971764946 |
| 21 | 7766890826 |
| 22 | 20131080168 |
| 23 | 51766513279 |
| 24 | 132117237595 |
| 25 | 334770353022 |
| 26 | 842462217948 |
| 27 | 2106183375971 |
| 28 | 5232414548275 |
| 29 | 12920429411759 |
| 30 | 31719180847831 |
[1,1,8,30,108,357,1205,3838,12083,36896,110828, 326281,946086,2700026,7602642,21128513,58028309, 157588912,423534324,1127102360,2971764946, 7766890826,20131080168,51766513279,132117237595, 334770353022,842462217948,2106183375971, 5232414548275,12920429411759,31719180847831] |