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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 10 |
| 4 | 36 |
| 5 | 144 |
| 6 | 556 |
| 7 | 2172 |
| 8 | 8452 |
| 9 | 32932 |
| 10 | 128260 |
| 11 | 499604 |
| 12 | 1945988 |
| 13 | 7579860 |
| 14 | 29524324 |
| 15 | 115000436 |
| 16 | 447938884 |
| 17 | 1744769748 |
| 18 | 6796063908 |
| 19 | 26471392948 |
| 20 | 103108894980 |
| 21 | 401620128916 |
| 22 | 1564353180772 |
| 23 | 6093322268020 |
| 24 | 23734139269316 |
| 25 | 92447000518484 |
| 26 | 360090914096676 |
[0,1,2,10,36,144,556,2172,8452,32932,128260, 499604,1945988,7579860,29524324,115000436, 447938884,1744769748,6796063908,26471392948, 103108894980,401620128916,1564353180772, 6093322268020,23734139269316,92447000518484, 360090914096676] |