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| n | a(n) |
|---|---|
| 1 | 48 |
| 2 | 230 |
| 3 | 950 |
| 4 | 3632 |
| 5 | 13422 |
| 6 | 48542 |
| 7 | 173584 |
| 8 | 620100 |
| 9 | 2210560 |
| 10 | 7933738 |
| 11 | 28500322 |
| 12 | 103284630 |
| 13 | 374776104 |
| 14 | 1371409876 |
| 15 | 5022197054 |
| 16 | 18526229324 |
| 17 | 68352157746 |
| 18 | 253717012028 |
| 19 | 941511432258 |
| 20 | 3511229532198 |
| 21 | 13087482838170 |
| 22 | 48979882211566 |
[48,230,950,3632,13422,48542,173584,620100, 2210560,7933738,28500322,103284630,374776104, 1371409876,5022197054,18526229324,68352157746, 253717012028,941511432258,3511229532198, 13087482838170,48979882211566] |