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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 342 |
| 2 | 23256 |
| 3 | 548454 |
| 4 | 5756202 |
| 5 | 33953760 |
| 6 | 145404264 |
| 7 | 501480756 |
| 8 | 1455087222 |
| 9 | 3744992834 |
| 10 | 8666394912 |
| 11 | 18652602708 |
| 12 | 37257431778 |
| 13 | 70992509796 |
| 14 | 127919023344 |
| 15 | 222954244860 |
| 16 | 372270931974 |
| 17 | 606984681420 |
| 18 | 955026275808 |
| 19 | 1477806578172 |
| 20 | 2218909983696 |
| 21 | 3290673763164 |
[1,342,23256,548454,5756202,33953760,145404264, 501480756,1455087222,3744992834,8666394912, 18652602708,37257431778,70992509796,127919023344, 222954244860,372270931974,606984681420, 955026275808,1477806578172,2218909983696, 3290673763164] |