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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 12 |
| 4 | 1993 |
| 5 | 67098768 |
| 6 | 144115187673233113 |
| 7 | 1329227995784915871895000745158568460 |
| 8 | 226156424291633194186662080095093570015284114833799899660370362545578585265 |
[1,0,1,12,1993,67098768,144115187673233113, 1329227995784915871895000745158568460, 22615642429163319418666208009509357001528411483379\ 9899660370362545578585265] |