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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 11 |
| 6 | 30 |
| 7 | 122 |
| 8 | 336 |
| 9 | 1412 |
| 10 | 15129 |
| 11 | 44561 |
| 12 | 417542 |
| 13 | 2479120 |
| 14 | 7540843 |
| 15 | 35983502 |
| 16 | 451454834 |
| 17 | 5313515136 |
| 18 | 16809858904 |
| 19 | 190077477328 |
| 20 | 1124302066470 |
| 21 | 3521811953565 |
| 22 | 38563707677633 |
| 23 | 240966297786218 |
| 24 | 3192420711942298 |
| 25 | 95433674596402663 |
| 26 | 567734580765228356 |
[1,1,2,4,11,30,122,336,1412,15129,44561,417542, 2479120,7540843,35983502,451454834,5313515136, 16809858904,190077477328,1124302066470, 3521811953565,38563707677633,240966297786218, 3192420711942298,95433674596402663, 567734580765228356] |