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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 9 |
| 3 | 44 |
| 4 | 164 |
| 5 | 485 |
| 6 | 1278 |
| 7 | 2949 |
| 8 | 6382 |
| 9 | 12661 |
| 10 | 24101 |
| 11 | 43063 |
| 12 | 74932 |
| 13 | 124041 |
| 14 | 201597 |
| 15 | 315048 |
| 16 | 485627 |
| 17 | 724514 |
| 18 | 1071104 |
| 19 | 1539099 |
| 20 | 2197385 |
| 21 | 3062512 |
| 22 | 4246873 |
| 23 | 5765303 |
| 24 | 7804391 |
| 25 | 10359671 |
| 26 | 13728320 |
| 27 | 17882076 |
| 28 | 23264374 |
| 29 | 29792631 |
| 30 | 38154696 |
[0,1,9,44,164,485,1278,2949,6382,12661,24101, 43063,74932,124041,201597,315048,485627,724514, 1071104,1539099,2197385,3062512,4246873,5765303, 7804391,10359671,13728320,17882076,23264374, 29792631,38154696] |