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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 48 |
| 5 | 231 |
| 6 | 1198 |
| 7 | 6571 |
| 8 | 37708 |
| 9 | 224612 |
| 10 | 1381047 |
| 11 | 8728357 |
| 12 | 56520580 |
| 13 | 374049962 |
| 14 | 2524760084 |
| 15 | 17352434291 |
| 16 | 121271358844 |
| 17 | 860832917836 |
| 18 | 6200469605740 |
| 19 | 45281350853036 |
| 20 | 335040385844140 |
| 21 | 2510109678504943 |
| 22 | 19031562100423046 |
| 23 | 145961670086604701 |
| 24 | 1131893950714288692 |
| 25 | 8871861944975204172 |
[1,1,3,11,48,231,1198,6571,37708,224612,1381047, 8728357,56520580,374049962,2524760084,17352434291, 121271358844,860832917836,6200469605740, 45281350853036,335040385844140,2510109678504943, 19031562100423046,145961670086604701, 1131893950714288692,8871861944975204172] |