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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 22 |
| 2 | 190 |
| 3 | 1015 |
| 4 | 4018 |
| 5 | 12936 |
| 6 | 35784 |
| 7 | 88110 |
| 8 | 197835 |
| 9 | 412126 |
| 10 | 806806 |
| 11 | 1498861 |
| 12 | 2662660 |
| 13 | 4550560 |
| 14 | 7518624 |
| 15 | 12058236 |
| 16 | 18834453 |
| 17 | 28731990 |
| 18 | 42909790 |
| 19 | 62865187 |
| 20 | 90508726 |
| 21 | 128250760 |
| 22 | 179101000 |
| 23 | 246782250 |
| 24 | 335859615 |
| 25 | 451886526 |
| 26 | 601568982 |
[1,22,190,1015,4018,12936,35784,88110,197835, 412126,806806,1498861,2662660,4550560,7518624, 12058236,18834453,28731990,42909790,62865187, 90508726,128250760,179101000,246782250,335859615, 451886526,601568982] |