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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 15 |
| 6 | 30 |
| 7 | 113 |
| 8 | 226 |
| 9 | 897 |
| 10 | 3372 |
| 11 | 13821 |
| 12 | 54535 |
| 13 | 410690 |
| 14 | 1677109 |
| 15 | 13057708 |
| 16 | 99242206 |
| 17 | 798041029 |
| 18 | 6266181287 |
| 19 | 94041421473 |
| 20 | 762970233334 |
| 21 | 11832424270090 |
| 22 | 179170668019138 |
| 23 | 2871889457030716 |
| 24 | 44959471542344339 |
| 25 | 1344474186700872579 |
[1,2,2,4,8,15,30,113,226,897,3372,13821,54535, 410690,1677109,13057708,99242206,798041029, 6266181287,94041421473,762970233334, 11832424270090,179170668019138,2871889457030716, 44959471542344339,1344474186700872579] |