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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 2 |
| 4 | 7 |
| 5 | 31 |
| 6 | 167 |
| 7 | 1046 |
| 8 | 7949 |
| 9 | 60487 |
| 10 | 490753 |
| 11 | 4232323 |
| 12 | 39877499 |
| 13 | 401064825 |
| 14 | 4191449438 |
| 15 | 45993709856 |
| 16 | 526379057073 |
| 17 | 6284584514360 |
| 18 | 77594053714675 |
| 19 | 990497759689341 |
| 20 | 13053609492660678 |
| 21 | 177385290308586391 |
| 22 | 2480368806876623852 |
| 23 | 35617209442716039028 |
| 24 | 524705024124493308382 |
[1,1,0,2,7,31,167,1046,7949,60487,490753,4232323, 39877499,401064825,4191449438,45993709856, 526379057073,6284584514360,77594053714675, 990497759689341,13053609492660678, 177385290308586391,2480368806876623852, 35617209442716039028,524705024124493308382] |