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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 42 |
| 3 | 140 |
| 4 | 378 |
| 5 | 882 |
| 6 | 1848 |
| 7 | 3564 |
| 8 | 6435 |
| 9 | 11011 |
| 10 | 18018 |
| 11 | 28392 |
| 12 | 43316 |
| 13 | 64260 |
| 14 | 93024 |
| 15 | 131784 |
| 16 | 183141 |
| 17 | 250173 |
| 18 | 336490 |
| 19 | 446292 |
| 20 | 584430 |
| 21 | 756470 |
| 22 | 968760 |
| 23 | 1228500 |
| 24 | 1543815 |
| 25 | 1923831 |
| 26 | 2378754 |
| 27 | 2919952 |
| 28 | 3560040 |
| 29 | 4312968 |
| 30 | 5194112 |
| 31 | 6220368 |
| 32 | 7410249 |
| 33 | 8783985 |
| 34 | 10363626 |
[1,9,42,140,378,882,1848,3564,6435,11011,18018, 28392,43316,64260,93024,131784,183141,250173, 336490,446292,584430,756470,968760,1228500, 1543815,1923831,2378754,2919952,3560040,4312968, 5194112,6220368,7410249,8783985,10363626] |