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| n | a(n) |
|---|---|
| 1 | 10240 |
| 2 | 54212 |
| 3 | 312322 |
| 4 | 978154 |
| 5 | 2647806 |
| 6 | 7796356 |
| 7 | 20277514 |
| 8 | 50757141 |
| 9 | 124775368 |
| 10 | 293581128 |
| 11 | 660747412 |
| 12 | 1455827541 |
| 13 | 3098474026 |
| 14 | 6387841207 |
| 15 | 12869403490 |
| 16 | 25261405390 |
| 17 | 48376904916 |
| 18 | 90820987001 |
| 19 | 167055923784 |
| 20 | 301392610641 |
[10240,54212,312322,978154,2647806,7796356, 20277514,50757141,124775368,293581128,660747412, 1455827541,3098474026,6387841207,12869403490, 25261405390,48376904916,90820987001,167055923784, 301392610641] |