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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 36 |
| 4 | 148 |
| 5 | 498 |
| 6 | 1590 |
| 7 | 4586 |
| 8 | 12644 |
| 9 | 32775 |
| 10 | 81901 |
| 11 | 196085 |
| 12 | 455772 |
| 13 | 1025779 |
| 14 | 2252674 |
| 15 | 4823546 |
| 16 | 10116553 |
| 17 | 20783490 |
| 18 | 41949270 |
| 19 | 83211931 |
| 20 | 162552093 |
| 21 | 312850854 |
| 22 | 594086542 |
| 23 | 1113610526 |
| 24 | 2062796698 |
| 25 | 3777567977 |
| 26 | 6844786250 |
| 27 | 12276620372 |
| 28 | 21809737429 |
| 29 | 38391720375 |
[1,1,8,36,148,498,1590,4586,12644,32775,81901, 196085,455772,1025779,2252674,4823546,10116553, 20783490,41949270,83211931,162552093,312850854, 594086542,1113610526,2062796698,3777567977, 6844786250,12276620372,21809737429,38391720375] |