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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 19 |
| 4 | 65 |
| 5 | 211 |
| 6 | 665 |
| 7 | 2058 |
| 8 | 6294 |
| 9 | 19095 |
| 10 | 57607 |
| 11 | 173096 |
| 12 | 518596 |
| 13 | 1550367 |
| 14 | 4627455 |
| 15 | 13795176 |
| 16 | 41088456 |
| 17 | 122297643 |
| 18 | 363828663 |
| 19 | 1081966875 |
| 20 | 3216725841 |
| 21 | 9561635853 |
| 22 | 28418162003 |
| 23 | 84455354206 |
| 24 | 250982289650 |
| 25 | 745860104145 |
| 26 | 2216567725281 |
[1,5,19,65,211,665,2058,6294,19095,57607,173096, 518596,1550367,4627455,13795176,41088456, 122297643,363828663,1081966875,3216725841, 9561635853,28418162003,84455354206,250982289650, 745860104145,2216567725281] |