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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 29 |
| 5 | 63 |
| 6 | 572 |
| 7 | 1556 |
| 8 | 2013 |
| 9 | 2530 |
| 10 | 2760 |
| 11 | 3019 |
| 12 | 4159 |
| 13 | 4741 |
| 14 | 6820 |
| 15 | 10565 |
| 16 | 11666 |
| 17 | 32859 |
| 18 | 139893 |
| 19 | 392130 |
| 20 | 707970 |
| 21 | 1049722 |
| 22 | 2081165 |
| 23 | 14990404 |
| 24 | 36112276 |
| 25 | 39552835 |
| 26 | 42710787 |
| 27 | 199618806 |
[1,2,4,29,63,572,1556,2013,2530,2760,3019,4159, 4741,6820,10565,11666,32859,139893,392130,707970, 1049722,2081165,14990404,36112276,39552835, 42710787,199618806] |