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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 5 |
| 7 | 20 |
| 8 | 60 |
| 9 | 160 |
| 10 | 381 |
| 11 | 845 |
| 12 | 1760 |
| 13 | 3495 |
| 14 | 6660 |
| 15 | 12267 |
| 16 | 21935 |
| 17 | 38230 |
| 18 | 65140 |
| 19 | 108785 |
| 20 | 178437 |
| 21 | 287975 |
| 22 | 457965 |
| 23 | 718575 |
| 24 | 1113680 |
| 25 | 1706533 |
| 26 | 2587655 |
| 27 | 3885615 |
| 28 | 5781830 |
| 29 | 8530625 |
| 30 | 12486429 |
| 31 | 18140360 |
| 32 | 26169335 |
| 33 | 37501595 |
| 34 | 53403915 |
| 35 | 75597130 |
| 36 | 106408670 |
| 37 | 148973260 |
| 38 | 207496090 |
[1,5,20,60,160,381,845,1760,3495,6660,12267,21935, 38230,65140,108785,178437,287975,457965,718575, 1113680,1706533,2587655,3885615,5781830,8530625, 12486429,18140360,26169335,37501595,53403915, 75597130,106408670,148973260,207496090] |