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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 54 |
| 6 | 197 |
| 7 | 746 |
| 8 | 2876 |
| 9 | 11390 |
| 10 | 45977 |
| 11 | 188066 |
| 12 | 780848 |
| 13 | 3280312 |
| 14 | 13909971 |
| 15 | 59533135 |
| 16 | 256759223 |
| 17 | 1114687983 |
| 18 | 4869337791 |
| 19 | 21385124366 |
| 20 | 94368601473 |
| 21 | 418274225010 |
| 22 | 1861248654027 |
| 23 | 8311998648668 |
| 24 | 37242997500962 |
| 25 | 167375917694208 |
| 26 | 754308894036624 |
| 27 | 3408201201827853 |
| 28 | 15436011804303550 |
[1,1,2,5,16,54,197,746,2876,11390,45977,188066, 780848,3280312,13909971,59533135,256759223, 1114687983,4869337791,21385124366,94368601473, 418274225010,1861248654027,8311998648668, 37242997500962,167375917694208,754308894036624, 3408201201827853,15436011804303550] |