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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 80 |
| 5 | 363 |
| 6 | 1792 |
| 7 | 8969 |
| 8 | 46319 |
| 9 | 242994 |
| 10 | 1296046 |
| 11 | 6996163 |
| 12 | 38175142 |
| 13 | 210162728 |
| 14 | 1166020560 |
| 15 | 6512854409 |
| 16 | 36593709385 |
| 17 | 206686641555 |
| 18 | 1172856064443 |
| 19 | 6683348391034 |
| 20 | 38228129813288 |
| 21 | 219411037878578 |
| 22 | 1263245957786120 |
| 23 | 7293833100110787 |
| 24 | 42224142505632305 |
[1,1,5,17,80,363,1792,8969,46319,242994,1296046, 6996163,38175142,210162728,1166020560,6512854409, 36593709385,206686641555,1172856064443, 6683348391034,38228129813288,219411037878578, 1263245957786120,7293833100110787, 42224142505632305] |