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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 41 |
| 3 | 266 |
| 4 | 1247 |
| 5 | 4657 |
| 6 | 67537 |
| 7 | 433401 |
| 8 | 1481460 |
| 9 | 3510600 |
| 10 | 6637020 |
| 11 | 10878576 |
| 12 | 16235268 |
| 13 | 22707096 |
| 14 | 30294060 |
| 15 | 38996160 |
| 16 | 48813396 |
| 17 | 59745768 |
| 18 | 71793276 |
| 19 | 84955920 |
| 20 | 99233700 |
| 21 | 114626616 |
| 22 | 131134668 |
| 23 | 148757856 |
| 24 | 167496180 |
| 25 | 187349640 |
| 26 | 208318236 |
[6,41,266,1247,4657,67537,433401,1481460,3510600, 6637020,10878576,16235268,22707096,30294060, 38996160,48813396,59745768,71793276,84955920, 99233700,114626616,131134668,148757856,167496180, 187349640,208318236] |