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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 54 |
| 3 | 210 |
| 4 | 659 |
| 5 | 1772 |
| 6 | 4235 |
| 7 | 9218 |
| 8 | 18590 |
| 9 | 35178 |
| 10 | 63064 |
| 11 | 107910 |
| 12 | 177297 |
| 13 | 281060 |
| 14 | 431598 |
| 15 | 644136 |
| 16 | 936915 |
| 17 | 1331286 |
| 18 | 1851685 |
| 19 | 2525468 |
| 20 | 3382588 |
| 21 | 4455100 |
| 22 | 5776486 |
| 23 | 7380800 |
| 24 | 9301642 |
| 25 | 11570980 |
| 26 | 14217849 |
| 27 | 17266966 |
| 28 | 20737309 |
| 29 | 24640716 |
| 30 | 28980565 |
[1,10,54,210,659,1772,4235,9218,18590,35178,63064, 107910,177297,281060,431598,644136,936915,1331286, 1851685,2525468,3382588,4455100,5776486,7380800, 9301642,11570980,14217849,17266966,20737309, 24640716,28980565] |