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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 30 |
| 2 | 141 |
| 3 | 513 |
| 4 | 1815 |
| 5 | 5727 |
| 6 | 15882 |
| 7 | 42417 |
| 8 | 108165 |
| 9 | 255831 |
| 10 | 585258 |
| 11 | 1302966 |
| 12 | 2762349 |
| 13 | 5705829 |
| 14 | 11577633 |
| 15 | 22708053 |
| 16 | 43675938 |
| 17 | 83011398 |
| 18 | 153929484 |
| 19 | 281210994 |
| 20 | 509494515 |
| 21 | 905832642 |
| 22 | 1591395774 |
| 23 | 2778237765 |
| 24 | 4776943011 |
[3,30,141,513,1815,5727,15882,42417,108165,255831, 585258,1302966,2762349,5705829,11577633,22708053, 43675938,83011398,153929484,281210994,509494515, 905832642,1591395774,2778237765,4776943011] |