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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 201 |
| 3 | 1010 |
| 4 | 40601 |
| 5 | 204015 |
| 6 | 8201201 |
| 7 | 41210020 |
| 8 | 1656602001 |
| 9 | 8324220025 |
| 10 | 334625403001 |
| 11 | 1681451235030 |
| 12 | 67592674804201 |
| 13 | 339644825256035 |
| 14 | 13653385685045601 |
| 15 | 68606573250484040 |
| 16 | 2757916315704407201 |
| 17 | 13858188151772520045 |
| 18 | 557085442386605209001 |
[1,5,201,1010,40601,204015,8201201,41210020, 1656602001,8324220025,334625403001,1681451235030, 67592674804201,339644825256035,13653385685045601, 68606573250484040,2757916315704407201, 13858188151772520045,557085442386605209001] |