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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 8 |
| 5 | 32 |
| 6 | 141 |
| 7 | 749 |
| 8 | 4304 |
| 9 | 26492 |
| 10 | 169263 |
| 11 | 1115015 |
| 12 | 7507211 |
| 13 | 51466500 |
| 14 | 358100288 |
| 15 | 2523472751 |
| 16 | 17978488711 |
| 17 | 129325796854 |
| 18 | 938234533024 |
| 19 | 6858551493579 |
| 20 | 50478955083341 |
| 21 | 373815860588360 |
| 22 | 2783730088637429 |
| 23 | 20835514668765200 |
| 24 | 156675846789962554 |
| 25 | 1183195305751233833 |
[1,1,1,3,8,32,141,749,4304,26492,169263,1115015, 7507211,51466500,358100288,2523472751,17978488711, 129325796854,938234533024,6858551493579, 50478955083341,373815860588360,2783730088637429, 20835514668765200,156675846789962554, 1183195305751233833] |