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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 14 |
| 5 | 35 |
| 6 | 84 |
| 7 | 204 |
| 8 | 492 |
| 9 | 1189 |
| 10 | 2870 |
| 11 | 6930 |
| 12 | 16730 |
| 13 | 40391 |
| 14 | 97512 |
| 15 | 235416 |
| 16 | 568344 |
| 17 | 1372105 |
| 18 | 3312554 |
| 19 | 7997214 |
| 20 | 19306982 |
| 21 | 46611179 |
| 22 | 112529340 |
| 23 | 271669860 |
| 24 | 655869060 |
| 25 | 1583407981 |
| 26 | 3822685022 |
| 27 | 9228778026 |
| 28 | 22280241074 |
| 29 | 53789260175 |
| 30 | 129858761424 |
| 31 | 313506783024 |
[0,1,2,6,14,35,84,204,492,1189,2870,6930,16730, 40391,97512,235416,568344,1372105,3312554,7997214, 19306982,46611179,112529340,271669860,655869060, 1583407981,3822685022,9228778026,22280241074, 53789260175,129858761424,313506783024] |