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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 44 |
| 6 | 168 |
| 7 | 716 |
| 8 | 3331 |
| 9 | 16599 |
| 10 | 87059 |
| 11 | 473569 |
| 12 | 2641428 |
| 13 | 14982656 |
| 14 | 85930423 |
| 15 | 496412949 |
| 16 | 2881216925 |
| 17 | 16773626497 |
| 18 | 97843056510 |
| 19 | 571457023718 |
| 20 | 3340356838651 |
| 21 | 19535838889479 |
| 22 | 114293073644447 |
| 23 | 668811749036809 |
| 24 | 3914263576403496 |
[1,2,5,13,44,168,716,3331,16599,87059,473569, 2641428,14982656,85930423,496412949,2881216925, 16773626497,97843056510,571457023718, 3340356838651,19535838889479,114293073644447, 668811749036809,3914263576403496] |