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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 5 |
| 4 | 7 |
| 5 | 18 |
| 6 | 55 |
| 7 | 172 |
| 8 | 575 |
| 9 | 1962 |
| 10 | 6756 |
| 11 | 23400 |
| 12 | 81288 |
| 13 | 283089 |
| 14 | 987275 |
| 15 | 3444621 |
| 16 | 12023434 |
| 17 | 41982749 |
| 18 | 146612525 |
| 19 | 512036344 |
| 20 | 1788383898 |
| 21 | 6246509941 |
| 22 | 21818284060 |
| 23 | 76209472929 |
| 24 | 266195826556 |
| 25 | 929812279542 |
| 26 | 3247807389634 |
| 27 | 11344517688838 |
[1,13,5,7,18,55,172,575,1962,6756,23400,81288, 283089,987275,3444621,12023434,41982749,146612525, 512036344,1788383898,6246509941,21818284060, 76209472929,266195826556,929812279542, 3247807389634,11344517688838] |