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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 61 |
| 5 | 201 |
| 6 | 945 |
| 7 | 3453 |
| 8 | 16293 |
| 9 | 63145 |
| 10 | 298781 |
| 11 | 1202799 |
| 12 | 5703523 |
| 13 | 23577447 |
| 14 | 111992747 |
| 15 | 472089081 |
| 16 | 2245549141 |
| 17 | 9608529475 |
| 18 | 45757357387 |
| 19 | 198121904171 |
| 20 | 944424232919 |
| 21 | 4128557781623 |
| 22 | 19697281953755 |
| 23 | 86790670454669 |
| 24 | 414390032409781 |
| 25 | 1838063755309025 |
| 26 | 8781911972684573 |
| 27 | 39173855467598759 |
[1,1,5,13,61,201,945,3453,16293,63145,298781, 1202799,5703523,23577447,111992747,472089081, 2245549141,9608529475,45757357387,198121904171, 944424232919,4128557781623,19697281953755, 86790670454669,414390032409781,1838063755309025, 8781911972684573,39173855467598759] |