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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 11 |
| 4 | 34 |
| 5 | 104 |
| 6 | 313 |
| 7 | 938 |
| 8 | 2812 |
| 9 | 8435 |
| 10 | 25306 |
| 11 | 75920 |
| 12 | 227761 |
| 13 | 683282 |
| 14 | 2049844 |
| 15 | 6149531 |
| 16 | 18448594 |
| 17 | 55345784 |
| 18 | 166037353 |
| 19 | 498112058 |
| 20 | 1494336172 |
| 21 | 4483008515 |
| 22 | 13449025546 |
| 23 | 40347076640 |
| 24 | 121041229921 |
| 25 | 363123689762 |
| 26 | 1089371069284 |
[1,2,4,11,34,104,313,938,2812,8435,25306,75920, 227761,683282,2049844,6149531,18448594,55345784, 166037353,498112058,1494336172,4483008515, 13449025546,40347076640,121041229921,363123689762, 1089371069284] |