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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 41 |
| 5 | 103 |
| 6 | 263 |
| 7 | 656 |
| 8 | 1618 |
| 9 | 3931 |
| 10 | 9459 |
| 11 | 22557 |
| 12 | 53395 |
| 13 | 125594 |
| 14 | 293796 |
| 15 | 683972 |
| 16 | 1585588 |
| 17 | 3661900 |
| 18 | 8428646 |
| 19 | 19341455 |
| 20 | 44261305 |
| 21 | 101034472 |
| 22 | 230100558 |
| 23 | 522936849 |
| 24 | 1186138105 |
| 25 | 2685582035 |
| 26 | 6070360107 |
| 27 | 13699764020 |
| 28 | 30873005212 |
| 29 | 69478759648 |
[1,2,12,41,103,263,656,1618,3931,9459,22557,53395, 125594,293796,683972,1585588,3661900,8428646, 19341455,44261305,101034472,230100558,522936849, 1186138105,2685582035,6070360107,13699764020, 30873005212,69478759648] |