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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 21 |
| 3 | 96 |
| 4 | 441 |
| 5 | 2021 |
| 6 | 9261 |
| 7 | 42439 |
| 8 | 194481 |
| 9 | 891224 |
| 10 | 4084101 |
| 11 | 18715702 |
| 12 | 85766121 |
| 13 | 393029742 |
| 14 | 1801088541 |
| 15 | 8253624572 |
| 16 | 37822859361 |
| 17 | 173326116021 |
| 18 | 794280046581 |
| 19 | 3639848436450 |
| 20 | 16679880978201 |
| 21 | 76436817165460 |
| 22 | 350277500542221 |
| 23 | 1605173160474663 |
| 24 | 7355827511386641 |
[1,5,21,96,441,2021,9261,42439,194481,891224, 4084101,18715702,85766121,393029742,1801088541, 8253624572,37822859361,173326116021,794280046581, 3639848436450,16679880978201,76436817165460, 350277500542221,1605173160474663,7355827511386641] |