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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 42 |
| 2 | 902 |
| 3 | 13202 |
| 4 | 148091 |
| 5 | 1357468 |
| 6 | 10587675 |
| 7 | 72245074 |
| 8 | 440091498 |
| 9 | 2430433874 |
| 10 | 12315996232 |
| 11 | 57824666110 |
| 12 | 253554446677 |
| 13 | 1045266952884 |
| 14 | 4073988274266 |
| 15 | 15084671038416 |
| 16 | 53281879968821 |
| 17 | 180187334962466 |
| 18 | 585265396834041 |
[1,42,902,13202,148091,1357468,10587675,72245074, 440091498,2430433874,12315996232,57824666110, 253554446677,1045266952884,4073988274266, 15084671038416,53281879968821,180187334962466, 585265396834041] |