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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 12 |
| 4 | 1 |
| 5 | 133 |
| 6 | 1596 |
| 7 | 1 |
| 8 | 1464 |
| 9 | 16226 |
| 10 | 194712 |
| 11 | 2336544 |
| 12 | 1 |
| 13 | 16105 |
| 14 | 1964810 |
| 15 | 23577720 |
| 16 | 261319730 |
| 17 | 3135836760 |
| 18 | 37630041120 |
| 19 | 1 |
| 20 | 177156 |
| 21 | 237758115 |
| 22 | 2617126920 |
| 23 | 2853097380 |
| 24 | 348077880360 |
| 25 | 3857863173990 |
| 26 | 4176934564320 |
| 27 | 46294358087880 |
| 28 | 555532297054560 |
| 29 | 6666387564654720 |
| 30 | 1 |
| 31 | 1948717 |
[1,1,12,1,133,1596,1,1464,16226,194712,2336544,1, 16105,1964810,23577720,261319730,3135836760, 37630041120,1,177156,237758115,2617126920, 2853097380,348077880360,3857863173990, 4176934564320,46294358087880,555532297054560, 6666387564654720,1,1948717] |