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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 29 |
| 5 | 78 |
| 6 | 338 |
| 7 | 1058 |
| 8 | 4686 |
| 9 | 15803 |
| 10 | 71729 |
| 11 | 253562 |
| 12 | 1169404 |
| 13 | 4288926 |
| 14 | 19974730 |
| 15 | 75412117 |
| 16 | 353859401 |
| 17 | 1366111116 |
| 18 | 6451741800 |
| 19 | 25355370298 |
| 20 | 120372620960 |
| 21 | 480181343782 |
| 22 | 2289045790648 |
| 23 | 9247921966268 |
| 24 | 44237902037162 |
| 25 | 180665568976249 |
| 26 | 866824352303161 |
| 27 | 3573205164846309 |
| 28 | 17188580145141317 |
[1,1,3,7,29,78,338,1058,4686,15803,71729,253562, 1169404,4288926,19974730,75412117,353859401, 1366111116,6451741800,25355370298,120372620960, 480181343782,2289045790648,9247921966268, 44237902037162,180665568976249,866824352303161, 3573205164846309,17188580145141317] |