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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 22 |
| 4 | 22 |
| 5 | 22 |
| 6 | 508 |
| 7 | 508 |
| 8 | 2695 |
| 9 | 2695 |
| 10 | 2695 |
| 11 | 2695 |
| 12 | 356989 |
| 13 | 888430 |
| 14 | 4077076 |
| 15 | 4077076 |
| 16 | 18425983 |
| 17 | 18425983 |
| 18 | 147566146 |
| 19 | 534986635 |
| 20 | 534986635 |
| 21 | 7508555437 |
| 22 | 28429261843 |
| 23 | 28429261843 |
| 24 | 122572440670 |
| 25 | 405001977151 |
[0,1,4,22,22,22,508,508,2695,2695,2695,2695, 356989,888430,4077076,4077076,18425983,18425983, 147566146,534986635,534986635,7508555437, 28429261843,28429261843,122572440670,405001977151] |