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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 35 |
| 4 | 115 |
| 5 | 339 |
| 6 | 1043 |
| 7 | 2963 |
| 8 | 8595 |
| 9 | 23955 |
| 10 | 66963 |
| 11 | 181651 |
| 12 | 497043 |
| 13 | 1324435 |
| 14 | 3536275 |
| 15 | 9303443 |
| 16 | 24442259 |
| 17 | 63370643 |
| 18 | 164296083 |
| 19 | 421197203 |
| 20 | 1078654355 |
| 21 | 2739598739 |
| 22 | 6942291347 |
| 23 | 17469994387 |
| 24 | 43894109587 |
| 25 | 109593687443 |
| 26 | 273070880147 |
| 27 | 677066241427 |
| 28 | 1675109266835 |
[1,3,11,35,115,339,1043,2963,8595,23955,66963, 181651,497043,1324435,3536275,9303443,24442259, 63370643,164296083,421197203,1078654355, 2739598739,6942291347,17469994387,43894109587, 109593687443,273070880147,677066241427, 1675109266835] |