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| n | a(n) |
|---|---|
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 23 |
| 7 | 114 |
| 8 | 675 |
| 9 | 4357 |
| 10 | 29692 |
| 11 | 209933 |
| 12 | 1531349 |
| 13 | 11439545 |
| 14 | 87202034 |
| 15 | 676101375 |
| 16 | 5319069978 |
| 17 | 42378741675 |
| 18 | 341403125204 |
| 19 | 2777329727768 |
| 20 | 22790623236250 |
| 21 | 188475690185517 |
| 22 | 1569588986566488 |
| 23 | 13153980294670851 |
| 24 | 110870960421707325 |
| 25 | 939397206702263021 |
[1,2,5,23,114,675,4357,29692,209933,1531349, 11439545,87202034,676101375,5319069978, 42378741675,341403125204,2777329727768, 22790623236250,188475690185517,1569588986566488, 13153980294670851,110870960421707325, 939397206702263021] |