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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 11 |
| 6 | 51 |
| 7 | 246 |
| 8 | 897 |
| 9 | 7085 |
| 10 | 51221 |
| 11 | 260426 |
| 12 | 2938541 |
| 13 | 28279967 |
| 14 | 184234415 |
| 15 | 2714662406 |
| 16 | 32614422401 |
| 17 | 259026339161 |
| 18 | 4721237878537 |
| 19 | 67998862785970 |
| 20 | 637019875964341 |
| 21 | 13852253151455251 |
| 22 | 232584488748665131 |
| 23 | 2510358957337412182 |
| 24 | 63466995535914172225 |
[1,1,1,2,5,11,51,246,897,7085,51221,260426, 2938541,28279967,184234415,2714662406,32614422401, 259026339161,4721237878537,67998862785970, 637019875964341,13852253151455251, 232584488748665131,2510358957337412182, 63466995535914172225] |