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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 26 |
| 4 | 75 |
| 5 | 196 |
| 6 | 520 |
| 7 | 1361 |
| 8 | 3570 |
| 9 | 9346 |
| 10 | 24475 |
| 11 | 64076 |
| 12 | 167760 |
| 13 | 439201 |
| 14 | 1149850 |
| 15 | 3010346 |
| 16 | 7881195 |
| 17 | 20633236 |
| 18 | 54018520 |
| 19 | 141422321 |
| 20 | 370248450 |
| 21 | 969323026 |
| 22 | 2537720635 |
| 23 | 6643838876 |
| 24 | 17393796000 |
| 25 | 45537549121 |
| 26 | 119218851370 |
[1,10,26,75,196,520,1361,3570,9346,24475,64076, 167760,439201,1149850,3010346,7881195,20633236, 54018520,141422321,370248450,969323026,2537720635, 6643838876,17393796000,45537549121,119218851370] |