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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 2 |
| 3 | 17 |
| 4 | 18 |
| 5 | 67 |
| 6 | 104 |
| 7 | 287 |
| 8 | 532 |
| 9 | 1289 |
| 10 | 2598 |
| 11 | 5933 |
| 12 | 12438 |
| 13 | 27639 |
| 14 | 59020 |
| 15 | 129499 |
| 16 | 278920 |
| 17 | 608397 |
| 18 | 1315658 |
| 19 | 2861929 |
| 20 | 6200506 |
| 21 | 13470635 |
| 22 | 29210224 |
| 23 | 63421623 |
| 24 | 137581660 |
| 25 | 298636305 |
| 26 | 647959662 |
| 27 | 1406286917 |
| 28 | 3051529598 |
| 29 | 6622430687 |
[1,5,2,17,18,67,104,287,532,1289,2598,5933,12438, 27639,59020,129499,278920,608397,1315658,2861929, 6200506,13470635,29210224,63421623,137581660, 298636305,647959662,1406286917,3051529598, 6622430687] |