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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 34 |
| 5 | 174 |
| 6 | 1047 |
| 7 | 7333 |
| 8 | 58665 |
| 9 | 527987 |
| 10 | 5279872 |
| 11 | 58078601 |
| 12 | 696943215 |
| 13 | 9060261802 |
| 14 | 126843665237 |
| 15 | 1902654978556 |
| 16 | 30442479656900 |
| 17 | 517522154167308 |
| 18 | 9315398775011558 |
| 19 | 176992576725219613 |
| 20 | 3539851534504392267 |
[1,2,8,34,174,1047,7333,58665,527987,5279872, 58078601,696943215,9060261802,126843665237, 1902654978556,30442479656900,517522154167308, 9315398775011558,176992576725219613, 3539851534504392267] |