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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 18 |
| 5 | 66 |
| 6 | 266 |
| 7 | 1111 |
| 8 | 4792 |
| 9 | 21124 |
| 10 | 94888 |
| 11 | 432415 |
| 12 | 1994828 |
| 13 | 9296712 |
| 14 | 43706722 |
| 15 | 207030398 |
| 16 | 987130456 |
| 17 | 4733961435 |
| 18 | 22819241034 |
| 19 | 110500644857 |
| 20 | 537295738556 |
| 21 | 2622248720234 |
| 22 | 12840953621208 |
| 23 | 63074566121245 |
| 24 | 310693364823376 |
| 25 | 1534374047239554 |
| 26 | 7595642577152762 |
[1,2,5,18,66,266,1111,4792,21124,94888,432415, 1994828,9296712,43706722,207030398,987130456, 4733961435,22819241034,110500644857,537295738556, 2622248720234,12840953621208,63074566121245, 310693364823376,1534374047239554,7595642577152762] |