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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 22 |
| 3 | 6 |
| 4 | 116 |
| 5 | 315 |
| 6 | 502 |
| 7 | 3630 |
| 8 | 7770 |
| 9 | 34645 |
| 10 | 86317 |
| 11 | 320622 |
| 12 | 966922 |
| 13 | 3306875 |
| 14 | 10609266 |
| 15 | 34934092 |
| 16 | 114138685 |
| 17 | 374143779 |
| 18 | 1227335831 |
| 19 | 4020363887 |
| 20 | 13193058120 |
| 21 | 43248448731 |
| 22 | 141915161267 |
| 23 | 465495771858 |
| 24 | 1527373960376 |
| 25 | 5011467375946 |
[0,22,6,116,315,502,3630,7770,34645,86317,320622, 966922,3306875,10609266,34934092,114138685, 374143779,1227335831,4020363887,13193058120, 43248448731,141915161267,465495771858, 1527373960376,5011467375946] |