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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 10 |
| 4 | 37 |
| 5 | 716 |
| 6 | 4741 |
| 7 | 136760 |
| 8 | 1314377 |
| 9 | 50468752 |
| 10 | 637409641 |
| 11 | 30580648352 |
| 12 | 479025538861 |
| 13 | 27578021183168 |
| 14 | 515932095998957 |
| 15 | 34657964676194176 |
| 16 | 754078761294069649 |
| 17 | 57902855910383448320 |
| 18 | 1436649321508321044817 |
| 19 | 124128617507138965088768 |
| 20 | 3459197142121422461242421 |
[1,1,1,10,37,716,4741,136760,1314377,50468752, 637409641,30580648352,479025538861,27578021183168, 515932095998957,34657964676194176, 754078761294069649,57902855910383448320, 1436649321508321044817,124128617507138965088768, 3459197142121422461242421] |