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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 16 |
| 5 | 45 |
| 6 | 136 |
| 7 | 434 |
| 8 | 1436 |
| 9 | 4869 |
| 10 | 16804 |
| 11 | 58795 |
| 12 | 208022 |
| 13 | 742911 |
| 14 | 2674452 |
| 15 | 9694858 |
| 16 | 35357684 |
| 17 | 129644805 |
| 18 | 477638716 |
| 19 | 1767263207 |
| 20 | 6564120438 |
| 21 | 24466267039 |
| 22 | 91482563660 |
| 23 | 343059613671 |
| 24 | 1289904147346 |
| 25 | 4861946401475 |
| 26 | 18367353072176 |
| 27 | 69533550916029 |
| 28 | 263747951750386 |
| 29 | 1002242216651395 |
| 30 | 3814986502092332 |
[1,2,6,16,45,136,434,1436,4869,16804,58795,208022, 742911,2674452,9694858,35357684,129644805, 477638716,1767263207,6564120438,24466267039, 91482563660,343059613671,1289904147346, 4861946401475,18367353072176,69533550916029, 263747951750386,1002242216651395,3814986502092332] |