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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 57 |
| 5 | 320 |
| 6 | 2065 |
| 7 | 14954 |
| 8 | 119585 |
| 9 | 1044184 |
| 10 | 9867633 |
| 11 | 100185294 |
| 12 | 1086173121 |
| 13 | 12510549116 |
| 14 | 152422123321 |
| 15 | 1956974934290 |
| 16 | 26391647743937 |
| 17 | 372769201632784 |
| 18 | 5500416368181921 |
| 19 | 84594395013757398 |
| 20 | 1353277808896178145 |
| 21 | 22476374660911200068 |
| 22 | 386925983827921358665 |
| 23 | 6893254434792968631674 |
[1,1,3,12,57,320,2065,14954,119585,1044184, 9867633,100185294,1086173121,12510549116, 152422123321,1956974934290,26391647743937, 372769201632784,5500416368181921, 84594395013757398,1353277808896178145, 22476374660911200068,386925983827921358665, 6893254434792968631674] |