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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 5 |
| 4 | 12 |
| 5 | 20 |
| 6 | 45 |
| 7 | 77 |
| 8 | 168 |
| 9 | 294 |
| 10 | 630 |
| 11 | 1122 |
| 12 | 2376 |
| 13 | 4290 |
| 14 | 9009 |
| 15 | 16445 |
| 16 | 34320 |
| 17 | 63206 |
| 18 | 131274 |
| 19 | 243542 |
| 20 | 503880 |
| 21 | 940576 |
| 22 | 1939938 |
| 23 | 3640210 |
| 24 | 7488432 |
| 25 | 14115100 |
| 26 | 28973100 |
| 27 | 54826020 |
| 28 | 112326480 |
| 29 | 213286590 |
| 30 | 436268025 |
| 31 | 830905245 |
| 32 | 1697168160 |
| 33 | 3241119750 |
| 34 | 6611884290 |
[1,3,5,12,20,45,77,168,294,630,1122,2376,4290, 9009,16445,34320,63206,131274,243542,503880, 940576,1939938,3640210,7488432,14115100,28973100, 54826020,112326480,213286590,436268025,830905245, 1697168160,3241119750,6611884290] |