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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 34 |
| 5 | 466 |
| 6 | 9044 |
| 7 | 230827 |
| 8 | 7388781 |
| 9 | 287044354 |
| 10 | 13212057907 |
| 11 | 707417718215 |
| 12 | 43431362340153 |
| 13 | 3022050938855344 |
| 14 | 236053437141340206 |
| 15 | 20532456001485751429 |
| 16 | 1975258248906891145913 |
| 17 | 208928124926501980596761 |
| 18 | 24172548454436633069025270 |
[1,1,4,34,466,9044,230827,7388781,287044354, 13212057907,707417718215,43431362340153, 3022050938855344,236053437141340206, 20532456001485751429,1975258248906891145913, 208928124926501980596761, 24172548454436633069025270] |