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| n | a(n) |
|---|---|
| 4 | 1 |
| 5 | 5 |
| 6 | 5 |
| 7 | 15 |
| 8 | 40 |
| 9 | 15 |
| 10 | 35 |
| 11 | 175 |
| 12 | 175 |
| 13 | 35 |
| 14 | 70 |
| 15 | 560 |
| 16 | 1050 |
| 17 | 560 |
| 18 | 70 |
| 19 | 126 |
| 20 | 1470 |
| 21 | 4410 |
| 22 | 4410 |
| 23 | 1470 |
| 24 | 126 |
| 25 | 210 |
| 26 | 3360 |
| 27 | 14700 |
| 28 | 23520 |
| 29 | 14700 |
| 30 | 3360 |
| 31 | 210 |
| 32 | 330 |
| 33 | 6930 |
| 34 | 41580 |
| 35 | 97020 |
| 36 | 97020 |
| 37 | 41580 |
| 38 | 6930 |
| 39 | 330 |
| 40 | 495 |
| 41 | 13200 |
| 42 | 103950 |
| 43 | 332640 |
| 44 | 485100 |
| 45 | 332640 |
| 46 | 103950 |
| 47 | 13200 |
| 48 | 495 |
[1,5,5,15,40,15,35,175,175,35,70,560,1050,560,70, 126,1470,4410,4410,1470,126,210,3360,14700,23520, 14700,3360,210,330,6930,41580,97020,97020,41580, 6930,330,495,13200,103950,332640,485100,332640, 103950,13200,495] |