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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 34 |
| 4 | 155 |
| 5 | 720 |
| 6 | 3415 |
| 7 | 16388 |
| 8 | 79376 |
| 9 | 386810 |
| 10 | 1893990 |
| 11 | 9307399 |
| 12 | 45868921 |
| 13 | 226559511 |
| 14 | 1121063963 |
| 15 | 5555392199 |
| 16 | 27562783292 |
| 17 | 136888378457 |
| 18 | 680415457856 |
| 19 | 3384453591042 |
| 20 | 16844714507713 |
| 21 | 83880626917644 |
| 22 | 417879783643896 |
| 23 | 2082604380577140 |
| 24 | 10382601987269548 |
| 25 | 51776341640782272 |
| 26 | 258265723235989231 |
[1,2,8,34,155,720,3415,16388,79376,386810,1893990, 9307399,45868921,226559511,1121063963,5555392199, 27562783292,136888378457,680415457856, 3384453591042,16844714507713,83880626917644, 417879783643896,2082604380577140, 10382601987269548,51776341640782272, 258265723235989231] |