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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 16 |
| 3 | 62 |
| 4 | 220 |
| 5 | 812 |
| 6 | 2944 |
| 7 | 10760 |
| 8 | 39184 |
| 9 | 142928 |
| 10 | 520960 |
| 11 | 1899488 |
| 12 | 6924736 |
| 13 | 25246400 |
| 14 | 92041216 |
| 15 | 335560832 |
| 16 | 1223368960 |
| 17 | 4460102912 |
| 18 | 16260419584 |
| 19 | 59281456640 |
| 20 | 216125430784 |
| 21 | 787939601408 |
| 22 | 2872631787520 |
| 23 | 10472901183488 |
| 24 | 38181593092096 |
| 25 | 139200593285120 |
[1,5,16,62,220,812,2944,10760,39184,142928,520960, 1899488,6924736,25246400,92041216,335560832, 1223368960,4460102912,16260419584,59281456640, 216125430784,787939601408,2872631787520, 10472901183488,38181593092096,139200593285120] |