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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 40 |
| 3 | 1365 |
| 4 | 19448 |
| 5 | 381276 |
| 6 | 6615103 |
| 7 | 120241980 |
| 8 | 2147070680 |
| 9 | 38600066517 |
| 10 | 692153278024 |
| 11 | 12423591148332 |
| 12 | 222908960952575 |
| 13 | 4000098954110700 |
| 14 | 71777766990248968 |
| 15 | 1288007282149222101 |
| 16 | 23112301389881302808 |
| 17 | 414733773612913239420 |
| 18 | 7442093184423393874495 |
| 19 | 133542960264663589170972 |
[12,40,1365,19448,381276,6615103,120241980, 2147070680,38600066517,692153278024, 12423591148332,222908960952575,4000098954110700, 71777766990248968,1288007282149222101, 23112301389881302808,414733773612913239420, 7442093184423393874495,133542960264663589170972] |