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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 223 |
| 3 | 3898 |
| 4 | 64453 |
| 5 | 1042868 |
| 6 | 16747743 |
| 7 | 268285422 |
| 8 | 4294211881 |
| 9 | 68715706984 |
| 10 | 1099492954547 |
| 11 | 17592094126818 |
| 12 | 281474526684989 |
| 13 | 4503597434338652 |
| 14 | 72057583394694855 |
| 15 | 1152921453139596758 |
| 16 | 18446743825630274641 |
| 17 | 295147903987017778256 |
| 18 | 4722366477153821698011 |
[1,12,223,3898,64453,1042868,16747743,268285422, 4294211881,68715706984,1099492954547, 17592094126818,281474526684989,4503597434338652, 72057583394694855,1152921453139596758, 18446743825630274641,295147903987017778256, 4722366477153821698011] |