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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 59 |
| 4 | 183 |
| 5 | 476 |
| 6 | 1108 |
| 7 | 2409 |
| 8 | 4993 |
| 9 | 10007 |
| 10 | 19559 |
| 11 | 37504 |
| 12 | 70832 |
| 13 | 132145 |
| 14 | 244029 |
| 15 | 446763 |
| 16 | 811847 |
| 17 | 1465676 |
| 18 | 2630836 |
| 19 | 4697945 |
| 20 | 8350305 |
| 21 | 14779671 |
| 22 | 26058903 |
| 23 | 45784224 |
| 24 | 80179968 |
| 25 | 139995361 |
| 26 | 243755533 |
| 27 | 423324539 |
| 28 | 733409943 |
[1,13,59,183,476,1108,2409,4993,10007,19559,37504, 70832,132145,244029,446763,811847,1465676,2630836, 4697945,8350305,14779671,26058903,45784224, 80179968,139995361,243755533,423324539,733409943] |