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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 9 |
| 5 | 14 |
| 6 | 48 |
| 7 | 75 |
| 8 | 275 |
| 9 | 429 |
| 10 | 1638 |
| 11 | 2548 |
| 12 | 9996 |
| 13 | 15504 |
| 14 | 62016 |
| 15 | 95931 |
| 16 | 389367 |
| 17 | 600875 |
| 18 | 2466750 |
| 19 | 3798795 |
| 20 | 15737865 |
| 21 | 24192090 |
| 22 | 100975680 |
| 23 | 154969620 |
| 24 | 650872404 |
| 25 | 997490844 |
| 26 | 4211628008 |
| 27 | 6446369400 |
| 28 | 27341497800 |
| 29 | 41802112192 |
| 30 | 177996090624 |
| 31 | 271861216539 |
| 32 | 1161588834303 |
| 33 | 1772528290407 |
| 34 | 7596549816030 |
| 35 | 11582393855305 |
[1,1,2,3,9,14,48,75,275,429,1638,2548,9996,15504, 62016,95931,389367,600875,2466750,3798795, 15737865,24192090,100975680,154969620,650872404, 997490844,4211628008,6446369400,27341497800, 41802112192,177996090624,271861216539, 1161588834303,1772528290407,7596549816030, 11582393855305] |