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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 14 |
| 4 | 30 |
| 5 | 60 |
| 6 | 120 |
| 7 | 220 |
| 8 | 402 |
| 9 | 710 |
| 10 | 1224 |
| 11 | 2064 |
| 12 | 3438 |
| 13 | 5596 |
| 14 | 9012 |
| 15 | 14304 |
| 16 | 22422 |
| 17 | 34740 |
| 18 | 53330 |
| 19 | 80960 |
| 20 | 121908 |
| 21 | 181976 |
| 22 | 269484 |
| 23 | 396072 |
| 24 | 578232 |
| 25 | 838258 |
| 26 | 1207896 |
| 27 | 1730058 |
| 28 | 2463900 |
| 29 | 3490020 |
| 30 | 4918572 |
| 31 | 6897012 |
| 32 | 9626610 |
| 33 | 13375776 |
| 34 | 18504852 |
| 35 | 25494456 |
| 36 | 34985530 |
[1,2,6,14,30,60,120,220,402,710,1224,2064,3438, 5596,9012,14304,22422,34740,53330,80960,121908, 181976,269484,396072,578232,838258,1207896, 1730058,2463900,3490020,4918572,6897012,9626610, 13375776,18504852,25494456,34985530] |