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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 44 |
| 3 | 216 |
| 4 | 1040 |
| 5 | 5024 |
| 6 | 24256 |
| 7 | 117120 |
| 8 | 565504 |
| 9 | 2730496 |
| 10 | 13184000 |
| 11 | 63657984 |
| 12 | 307367936 |
| 13 | 1484103680 |
| 14 | 7165886464 |
| 15 | 34599960576 |
| 16 | 167063388160 |
| 17 | 806653394944 |
| 18 | 3894867132416 |
| 19 | 18806082109440 |
| 20 | 90803796967424 |
| 21 | 438439516307456 |
[1,10,44,216,1040,5024,24256,117120,565504, 2730496,13184000,63657984,307367936,1484103680, 7165886464,34599960576,167063388160,806653394944, 3894867132416,18806082109440,90803796967424, 438439516307456] |