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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 6 |
| 5 | 27 |
| 6 | 134 |
| 7 | 138 |
| 8 | 168 |
| 9 | 363 |
| 10 | 1970 |
| 11 | 5329 |
| 12 | 738639 |
| 13 | 752491 |
| 14 | 848775 |
| 15 | 1803305 |
| 16 | 2420500 |
| 17 | 20412333 |
| 18 | 207691249 |
| 19 | 220455692 |
| 20 | 517921150 |
| 21 | 521602912 |
| 22 | 1149023650 |
| 23 | 1289986143 |
| 24 | 5963709738 |
| 25 | 6262635619 |
| 26 | 23831964366 |
| 27 | 79255202271 |
| 28 | 1970864394858 |
| 29 | 2255739204027 |
[0,1,4,6,27,134,138,168,363,1970,5329,738639, 752491,848775,1803305,2420500,20412333,207691249, 220455692,517921150,521602912,1149023650, 1289986143,5963709738,6262635619,23831964366, 79255202271,1970864394858,2255739204027] |