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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 10 |
| 3 | 47 |
| 4 | 152 |
| 5 | 609 |
| 6 | 2138 |
| 7 | 7466 |
| 8 | 25798 |
| 9 | 87397 |
| 10 | 293470 |
| 11 | 979311 |
| 12 | 3235714 |
| 13 | 10650401 |
| 14 | 34842532 |
| 15 | 113507950 |
| 16 | 368400482 |
| 17 | 1191351902 |
| 18 | 3841448788 |
| 19 | 12352142633 |
| 20 | 39620840414 |
| 21 | 126807886700 |
| 22 | 405026431154 |
| 23 | 1291283976919 |
| 24 | 4109819232304 |
[0,10,47,152,609,2138,7466,25798,87397,293470, 979311,3235714,10650401,34842532,113507950, 368400482,1191351902,3841448788,12352142633, 39620840414,126807886700,405026431154, 1291283976919,4109819232304] |