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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 16 |
| 5 | 126 |
| 6 | 946 |
| 7 | 11201 |
| 8 | 125609 |
| 9 | 1988645 |
| 10 | 29865749 |
| 11 | 592326527 |
| 12 | 11181850967 |
| 13 | 266546940947 |
| 14 | 6069884741155 |
| 15 | 169005305069771 |
| 16 | 4510734458734443 |
| 17 | 143664066858425883 |
| 18 | 4399531515393236907 |
| 19 | 157747037226275555718 |
| 20 | 5453223770914252146978 |
| 21 | 217372015577641986139848 |
| 22 | 8374038291341888594002908 |
| 23 | 367340884744321785348071011 |
| 24 | 15606634300050239405862650475 |
[1,1,4,16,126,946,11201,125609,1988645,29865749, 592326527,11181850967,266546940947,6069884741155, 169005305069771,4510734458734443, 143664066858425883,4399531515393236907, 157747037226275555718,5453223770914252146978, 217372015577641986139848, 8374038291341888594002908, 367340884744321785348071011, 15606634300050239405862650475] |