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| n | a(n) |
|---|---|
| 4 | 30 |
| 5 | 67 |
| 6 | 195 |
| 7 | 670 |
| 8 | 2623 |
| 9 | 11437 |
| 10 | 54692 |
| 11 | 283625 |
| 12 | 1581303 |
| 13 | 9413380 |
| 14 | 59497049 |
| 15 | 397402597 |
| 16 | 2794008798 |
| 17 | 20606565063 |
| 18 | 158955946879 |
| 19 | 1279119138486 |
| 20 | 10712907438835 |
| 21 | 93190762200361 |
| 22 | 840437752639132 |
| 23 | 7844783028326405 |
| 24 | 75673025264120531 |
| 25 | 753330825335964276 |
[30,67,195,670,2623,11437,54692,283625,1581303, 9413380,59497049,397402597,2794008798,20606565063, 158955946879,1279119138486,10712907438835, 93190762200361,840437752639132,7844783028326405, 75673025264120531,753330825335964276] |