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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 11 |
| 5 | 52 |
| 6 | 258 |
| 7 | 1343 |
| 8 | 7257 |
| 9 | 40275 |
| 10 | 228278 |
| 11 | 1315922 |
| 12 | 7691196 |
| 13 | 45473095 |
| 14 | 271482064 |
| 15 | 1634359974 |
| 16 | 9910367591 |
| 17 | 60474714189 |
| 18 | 371087272878 |
| 19 | 2288372703482 |
| 20 | 14174212020218 |
| 21 | 88145412404781 |
| 22 | 550128210470715 |
| 23 | 3444680265887877 |
| 24 | 21633697884627237 |
| 25 | 136238869051956545 |
| 26 | 860130515526195618 |
| 27 | 5442975808350831237 |
| 28 | 34517730741744461395 |
| 29 | 219338548934112758627 |
[1,1,3,11,52,258,1343,7257,40275,228278,1315922, 7691196,45473095,271482064,1634359974,9910367591, 60474714189,371087272878,2288372703482, 14174212020218,88145412404781,550128210470715, 3444680265887877,21633697884627237, 136238869051956545,860130515526195618, 5442975808350831237,34517730741744461395, 219338548934112758627] |