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| n | a(n) |
|---|---|
| 1 | 128 |
| 2 | 858 |
| 3 | 8324 |
| 4 | 98466 |
| 5 | 1250228 |
| 6 | 16448400 |
| 7 | 220603364 |
| 8 | 2995602834 |
| 9 | 41048196236 |
| 10 | 566597492178 |
| 11 | 7869683384900 |
| 12 | 109903205061360 |
| 13 | 1542297167382164 |
| 14 | 21736984452051810 |
| 15 | 307535339926640204 |
| 16 | 4365796637993895186 |
| 17 | 62162535924592508036 |
| 18 | 887421840845709378960 |
[128,858,8324,98466,1250228,16448400,220603364, 2995602834,41048196236,566597492178,7869683384900, 109903205061360,1542297167382164, 21736984452051810,307535339926640204, 4365796637993895186,62162535924592508036, 887421840845709378960] |