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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 13 |
| 6 | 51 |
| 7 | 601 |
| 8 | 4803 |
| 9 | 63673 |
| 10 | 775351 |
| 11 | 12186061 |
| 12 | 196158183 |
| 13 | 3661759333 |
| 14 | 72413918019 |
| 15 | 1583407093633 |
| 16 | 36916485570331 |
| 17 | 929770285841137 |
| 18 | 24904721121298671 |
| 19 | 711342228666833173 |
| 20 | 21502519995056598639 |
| 21 | 687345492498807434461 |
| 22 | 23135454269839313430715 |
| 23 | 818568166383797223246601 |
| 24 | 30357965273255025673685091 |
[1,0,1,1,13,51,601,4803,63673,775351,12186061, 196158183,3661759333,72413918019,1583407093633, 36916485570331,929770285841137,24904721121298671, 711342228666833173,21502519995056598639, 687345492498807434461,23135454269839313430715, 818568166383797223246601, 30357965273255025673685091] |