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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 21 |
| 3 | 69 |
| 4 | 258 |
| 5 | 963 |
| 6 | 3493 |
| 7 | 12860 |
| 8 | 47305 |
| 9 | 173498 |
| 10 | 637397 |
| 11 | 2341283 |
| 12 | 8597415 |
| 13 | 31576458 |
| 14 | 115970574 |
| 15 | 425911328 |
| 16 | 1564226500 |
| 17 | 5744847726 |
| 18 | 21098720647 |
| 19 | 77488048294 |
| 20 | 284585727060 |
| 21 | 1045180704781 |
| 22 | 3838572624574 |
| 23 | 14097695093525 |
| 24 | 51775756521020 |
[5,21,69,258,963,3493,12860,47305,173498,637397, 2341283,8597415,31576458,115970574,425911328, 1564226500,5744847726,21098720647,77488048294, 284585727060,1045180704781,3838572624574, 14097695093525,51775756521020] |