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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 54 |
| 4 | 6961 |
| 5 | 1233318 |
| 6 | 487047961 |
| 7 | 290742044714 |
| 8 | 347251334512896 |
| 9 | 683674076661539256 |
| 10 | 2495297738110474036224 |
| 11 | 14634026423059969492022144 |
| 12 | 156866160296614402006202168641 |
| 13 | 2612384850652790986902453089127552 |
| 14 | 74149419491027435547521058057290511849 |
| 15 | 3283295561194682488327071117265547706288707 |
[0,1,54,6961,1233318,487047961,290742044714, 347251334512896,683674076661539256, 2495297738110474036224,14634026423059969492022144, 156866160296614402006202168641, 2612384850652790986902453089127552, 74149419491027435547521058057290511849, 3283295561194682488327071117265547706288707] |