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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 35 |
| 4 | 126 |
| 5 | 462 |
| 6 | 1716 |
| 7 | 6435 |
| 8 | 24310 |
| 9 | 92378 |
| 10 | 352716 |
| 11 | 1352078 |
| 12 | 5200300 |
| 13 | 20058300 |
| 14 | 77558760 |
| 15 | 300540195 |
| 16 | 1166803110 |
| 17 | 4537567650 |
| 18 | 17672631900 |
| 19 | 68923264410 |
| 20 | 269128937220 |
| 21 | 1052049481860 |
| 22 | 4116715363800 |
| 23 | 16123801841550 |
| 24 | 63205303218876 |
| 25 | 247959266474052 |
[1,3,10,35,126,462,1716,6435,24310,92378,352716, 1352078,5200300,20058300,77558760,300540195, 1166803110,4537567650,17672631900,68923264410, 269128937220,1052049481860,4116715363800, 16123801841550,63205303218876,247959266474052] |