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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 30 |
| 6 | 93 |
| 7 | 297 |
| 8 | 971 |
| 9 | 3338 |
| 10 | 11610 |
| 11 | 41667 |
| 12 | 151870 |
| 13 | 560921 |
| 14 | 2109659 |
| 15 | 8004331 |
| 16 | 30762570 |
| 17 | 119322599 |
| 18 | 466458505 |
| 19 | 1840186572 |
| 20 | 7303994132 |
| 21 | 29192626506 |
| 22 | 117376023897 |
| 23 | 474341080495 |
| 24 | 1927412337418 |
| 25 | 7865914630990 |
| 26 | 32242731996163 |
| 27 | 132707758649954 |
| 28 | 548168330676156 |
| 29 | 2272568359911595 |
[1,1,2,4,11,30,93,297,971,3338,11610,41667,151870, 560921,2109659,8004331,30762570,119322599, 466458505,1840186572,7303994132,29192626506, 117376023897,474341080495,1927412337418, 7865914630990,32242731996163,132707758649954, 548168330676156,2272568359911595] |