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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 32 |
| 6 | 97 |
| 7 | 282 |
| 8 | 870 |
| 9 | 2870 |
| 10 | 9215 |
| 11 | 30571 |
| 12 | 106328 |
| 13 | 361324 |
| 14 | 1256426 |
| 15 | 4523643 |
| 16 | 15971258 |
| 17 | 57343994 |
| 18 | 211680313 |
| 19 | 767950799 |
| 20 | 2823061650 |
| 21 | 10618284888 |
| 22 | 39319704544 |
| 23 | 147172286980 |
| 24 | 561739600196 |
| 25 | 2113692222212 |
| 26 | 8025292111327 |
| 27 | 30995394823367 |
| 28 | 118139661528722 |
| 29 | 453789274312738 |
| 30 | 1769748668161067 |
[1,1,2,5,12,32,97,282,870,2870,9215,30571,106328, 361324,1256426,4523643,15971258,57343994, 211680313,767950799,2823061650,10618284888, 39319704544,147172286980,561739600196, 2113692222212,8025292111327,30995394823367, 118139661528722,453789274312738,1769748668161067] |