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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 35 |
| 5 | 126 |
| 6 | 456 |
| 7 | 1667 |
| 8 | 6147 |
| 9 | 22825 |
| 10 | 85228 |
| 11 | 319683 |
| 12 | 1203632 |
| 13 | 4546270 |
| 14 | 17218995 |
| 15 | 65372310 |
| 16 | 248705155 |
| 17 | 947926359 |
| 18 | 3618884895 |
| 19 | 13836004764 |
| 20 | 52968655260 |
| 21 | 203022926480 |
| 22 | 779008308235 |
| 23 | 2992051471500 |
| 24 | 11502445734096 |
| 25 | 44256184906376 |
| 26 | 170408995261326 |
[1,1,3,10,35,126,456,1667,6147,22825,85228,319683, 1203632,4546270,17218995,65372310,248705155, 947926359,3618884895,13836004764,52968655260, 203022926480,779008308235,2992051471500, 11502445734096,44256184906376,170408995261326] |