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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 25 |
| 4 | 73 |
| 5 | 170 |
| 6 | 468 |
| 7 | 1050 |
| 8 | 2799 |
| 9 | 6138 |
| 10 | 16043 |
| 11 | 34644 |
| 12 | 89390 |
| 13 | 190913 |
| 14 | 488285 |
| 15 | 1034228 |
| 16 | 2628861 |
| 17 | 5532322 |
| 18 | 14000177 |
| 19 | 29311171 |
| 20 | 73936801 |
| 21 | 154145390 |
| 22 | 387911301 |
| 23 | 805899231 |
| 24 | 2024537328 |
| 25 | 4193625311 |
| 26 | 10521409964 |
| 27 | 21738996250 |
[1,3,10,25,73,170,468,1050,2799,6138,16043,34644, 89390,190913,488285,1034228,2628861,5532322, 14000177,29311171,73936801,154145390,387911301, 805899231,2024537328,4193625311,10521409964, 21738996250] |