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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 10 |
| 4 | 37 |
| 5 | 151 |
| 6 | 674 |
| 7 | 3263 |
| 8 | 17007 |
| 9 | 94828 |
| 10 | 562594 |
| 11 | 3534961 |
| 12 | 23428397 |
| 13 | 163187870 |
| 14 | 1190538144 |
| 15 | 9066908419 |
| 16 | 71837342107 |
| 17 | 590009213152 |
| 18 | 5004416730974 |
| 19 | 43667740987637 |
| 20 | 390497323261737 |
| 21 | 3565602957116674 |
| 22 | 33130941174471484 |
| 23 | 312322981161532615 |
| 24 | 2979191694795132887 |
[1,2,3,10,37,151,674,3263,17007,94828,562594, 3534961,23428397,163187870,1190538144,9066908419, 71837342107,590009213152,5004416730974, 43667740987637,390497323261737,3565602957116674, 33130941174471484,312322981161532615, 2979191694795132887] |