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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 19 |
| 7 | 55 |
| 8 | 125 |
| 9 | 245 |
| 10 | 434 |
| 11 | 4060 |
| 12 | 21186 |
| 13 | 81212 |
| 14 | 254813 |
| 15 | 692678 |
| 16 | 1688555 |
| 17 | 3776432 |
| 18 | 60101767 |
| 19 | 511650887 |
| 20 | 3089821383 |
| 21 | 14824989723 |
| 22 | 60057570858 |
| 23 | 213302293918 |
| 24 | 681247718668 |
| 25 | 1992449334436 |
| 26 | 5409214694961 |
| 27 | 132273848506202 |
| 28 | 1692162553490943 |
[1,1,1,2,3,4,19,55,125,245,434,4060,21186,81212, 254813,692678,1688555,3776432,60101767,511650887, 3089821383,14824989723,60057570858,213302293918, 681247718668,1992449334436,5409214694961, 132273848506202,1692162553490943] |