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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 31 |
| 4 | 68 |
| 5 | 235 |
| 6 | 303 |
| 7 | 538 |
| 8 | 841 |
| 9 | 8107 |
| 10 | 8948 |
| 11 | 17055 |
| 12 | 26003 |
| 13 | 95064 |
| 14 | 216131 |
| 15 | 1175719 |
| 16 | 6094726 |
| 17 | 7270445 |
| 18 | 442321426 |
| 19 | 449591871 |
| 20 | 2690280781 |
| 21 | 13900995776 |
| 22 | 30492272333 |
| 23 | 105377812775 |
| 24 | 135870085108 |
| 25 | 241247897883 |
| 26 | 377117982991 |
| 27 | 3635309744802 |
| 28 | 4012427727793 |
[1,1,6,31,68,235,303,538,841,8107,8948,17055, 26003,95064,216131,1175719,6094726,7270445, 442321426,449591871,2690280781,13900995776, 30492272333,105377812775,135870085108, 241247897883,377117982991,3635309744802, 4012427727793] |