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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 140 |
| 4 | 385 |
| 5 | 2870 |
| 6 | 8555 |
| 7 | 29370 |
| 8 | 42925 |
| 9 | 93665 |
| 10 | 116795 |
| 11 | 149226 |
| 12 | 155155 |
| 13 | 348551 |
| 14 | 380380 |
| 15 | 414090 |
| 16 | 513590 |
| 17 | 1229305 |
| 18 | 1801800 |
| 19 | 2567895 |
| 20 | 2767905 |
| 21 | 3873301 |
| 22 | 3924830 |
| 23 | 5053620 |
| 24 | 6970150 |
| 25 | 17090486 |
| 26 | 18362930 |
| 27 | 23396450 |
| 28 | 31919165 |
| 29 | 39336465 |
| 30 | 41791750 |
[1,5,140,385,2870,8555,29370,42925,93665,116795, 149226,155155,348551,380380,414090,513590,1229305, 1801800,2567895,2767905,3873301,3924830,5053620, 6970150,17090486,18362930,23396450,31919165, 39336465,41791750] |