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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 16 |
| 4 | 149 |
| 5 | 1956 |
| 6 | 33487 |
| 7 | 710914 |
| 8 | 18051945 |
| 9 | 534541240 |
| 10 | 18111042971 |
| 11 | 691843182174 |
| 12 | 29448194808397 |
| 13 | 1383323874167860 |
| 14 | 71145082349453127 |
| 15 | 3979392388532436586 |
| 16 | 240697239447634403153 |
| 17 | 15667133474066968379376 |
| 18 | 1092794908568878699158835 |
| 19 | 81380508121010249600574646 |
[1,1,3,16,149,1956,33487,710914,18051945, 534541240,18111042971,691843182174,29448194808397, 1383323874167860,71145082349453127, 3979392388532436586,240697239447634403153, 15667133474066968379376,1092794908568878699158835, 81380508121010249600574646] |