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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 6 |
| 4 | 1 |
| 5 | 20 |
| 6 | 84 |
| 7 | 1 |
| 8 | 70 |
| 9 | 495 |
| 10 | 1820 |
| 11 | 1 |
| 12 | 252 |
| 13 | 3003 |
| 14 | 15504 |
| 15 | 53130 |
| 16 | 1 |
| 17 | 924 |
| 18 | 18564 |
| 19 | 134596 |
| 20 | 593775 |
| 21 | 1947792 |
| 22 | 1 |
| 23 | 3432 |
| 24 | 116280 |
| 25 | 1184040 |
| 26 | 6724520 |
| 27 | 26978328 |
| 28 | 85900584 |
| 29 | 1 |
| 30 | 12870 |
| 31 | 735471 |
| 32 | 10518300 |
| 33 | 76904685 |
| 34 | 377348994 |
| 35 | 1420494075 |
| 36 | 4426165368 |
| 37 | 1 |
| 38 | 48620 |
| 39 | 4686825 |
| 40 | 94143280 |
| 41 | 886163135 |
| 42 | 5317936260 |
| 43 | 23667689815 |
| 44 | 85113005120 |
| 45 | 260887834350 |
[1,1,6,1,20,84,1,70,495,1820,1,252,3003,15504, 53130,1,924,18564,134596,593775,1947792,1,3432, 116280,1184040,6724520,26978328,85900584,1,12870, 735471,10518300,76904685,377348994,1420494075, 4426165368,1,48620,4686825,94143280,886163135, 5317936260,23667689815,85113005120,260887834350] |