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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 61 |
| 4 | 295 |
| 5 | 1447 |
| 6 | 7151 |
| 7 | 35491 |
| 8 | 176597 |
| 9 | 880125 |
| 10 | 4390901 |
| 11 | 21920913 |
| 12 | 109486993 |
| 13 | 547018941 |
| 14 | 2733608905 |
| 15 | 13662695645 |
| 16 | 68294088535 |
| 17 | 341399727335 |
| 18 | 1706739347095 |
| 19 | 8532741458075 |
| 20 | 42660172763995 |
| 21 | 213287735579135 |
| 22 | 1066389745361635 |
| 23 | 5331765761680895 |
[1,3,13,61,295,1447,7151,35491,176597,880125, 4390901,21920913,109486993,547018941,2733608905, 13662695645,68294088535,341399727335, 1706739347095,8532741458075,42660172763995, 213287735579135,1066389745361635,5331765761680895] |