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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 177 |
| 3 | 5111 |
| 4 | 60962 |
| 5 | 430729 |
| 6 | 2158099 |
| 7 | 8488095 |
| 8 | 27903044 |
| 9 | 79895265 |
| 10 | 205033333 |
| 11 | 481386807 |
| 12 | 1049954918 |
| 13 | 2152397897 |
| 14 | 4185095383 |
| 15 | 7774354687 |
| 16 | 13878462600 |
| 17 | 23923217921 |
| 18 | 39978597945 |
| 19 | 64985300791 |
| 20 | 103041066666 |
| 21 | 159757914953 |
[1,177,5111,60962,430729,2158099,8488095,27903044, 79895265,205033333,481386807,1049954918, 2152397897,4185095383,7774354687,13878462600, 23923217921,39978597945,64985300791,103041066666, 159757914953] |