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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 21 |
| 7 | 233 |
| 8 | 10946 |
| 9 | 5702887 |
| 10 | 139583862445 |
| 11 | 1779979416004714189 |
| 12 | 555565404224292694404015791808 |
| 13 | 2211236406303914545699412969744873993387956988653 |
| 14 | 2746979206949941983182302875628764119171817307595766156998135811615145905740557 |
[0,1,1,1,2,5,21,233,10946,5702887,139583862445, 1779979416004714189, 555565404224292694404015791808, 2211236406303914545699412969744873993387956988653, 27469792069499419831823028756287641191718173075957\ 66156998135811615145905740557] |