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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 65 |
| 3 | 330 |
| 4 | 1430 |
| 5 | 5512 |
| 6 | 19415 |
| 7 | 63570 |
| 8 | 195910 |
| 9 | 573430 |
| 10 | 1605340 |
| 11 | 4322110 |
| 12 | 11240645 |
| 13 | 28341730 |
| 14 | 69488650 |
| 15 | 166096270 |
| 16 | 387890625 |
| 17 | 886698670 |
| 18 | 1987322415 |
| 19 | 4373271870 |
| 20 | 9461022285 |
| 21 | 20144164040 |
| 22 | 42254620785 |
| 23 | 87398226990 |
| 24 | 178396331100 |
| 25 | 359618772656 |
| 26 | 716409453320 |
[1,10,65,330,1430,5512,19415,63570,195910,573430, 1605340,4322110,11240645,28341730,69488650, 166096270,387890625,886698670,1987322415, 4373271870,9461022285,20144164040,42254620785, 87398226990,178396331100,359618772656, 716409453320] |