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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 3 |
| 2 | 18 |
| 3 | 68 |
| 4 | 443 |
| 5 | 1068 |
| 6 | 1068 |
| 7 | 32318 |
| 8 | 110443 |
| 9 | 1672943 |
| 10 | 3626068 |
| 11 | 23157318 |
| 12 | 120813568 |
| 13 | 1097376068 |
| 14 | 1097376068 |
| 15 | 19407922943 |
| 16 | 49925501068 |
| 17 | 355101282318 |
| 18 | 355101282318 |
| 19 | 15613890344818 |
| 20 | 15613890344818 |
| 21 | 110981321985443 |
[0,3,18,68,443,1068,1068,32318,110443,1672943, 3626068,23157318,120813568,1097376068,1097376068, 19407922943,49925501068,355101282318,355101282318, 15613890344818,15613890344818,110981321985443] |