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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 44 |
| 3 | 156 |
| 4 | 450 |
| 5 | 1122 |
| 6 | 2508 |
| 7 | 5148 |
| 8 | 9867 |
| 9 | 17875 |
| 10 | 30888 |
| 11 | 51272 |
| 12 | 82212 |
| 13 | 127908 |
| 14 | 193800 |
| 15 | 286824 |
| 16 | 415701 |
| 17 | 591261 |
| 18 | 826804 |
| 19 | 1138500 |
| 20 | 1545830 |
| 21 | 2072070 |
| 22 | 2744820 |
| 23 | 3596580 |
| 24 | 4665375 |
| 25 | 5995431 |
| 26 | 7637904 |
| 27 | 9651664 |
| 28 | 12104136 |
| 29 | 15072200 |
| 30 | 18643152 |
| 31 | 22915728 |
| 32 | 28001193 |
[1,9,44,156,450,1122,2508,5148,9867,17875,30888, 51272,82212,127908,193800,286824,415701,591261, 826804,1138500,1545830,2072070,2744820,3596580, 4665375,5995431,7637904,9651664,12104136,15072200, 18643152,22915728,28001193] |