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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 49 |
| 4 | 214 |
| 5 | 946 |
| 6 | 4304 |
| 7 | 19727 |
| 8 | 91830 |
| 9 | 429586 |
| 10 | 2028808 |
| 11 | 9615266 |
| 12 | 45859356 |
| 13 | 219301044 |
| 14 | 1053397024 |
| 15 | 5070299771 |
| 16 | 24485264294 |
| 17 | 118436821842 |
| 18 | 574327076360 |
| 19 | 2788765754222 |
| 20 | 13568119543636 |
| 21 | 66085999862556 |
| 22 | 322392161536992 |
| 23 | 1574222913418742 |
| 24 | 7696752549738556 |
| 25 | 37661385553835476 |
| 26 | 184479995723373904 |
[1,3,12,49,214,946,4304,19727,91830,429586, 2028808,9615266,45859356,219301044,1053397024, 5070299771,24485264294,118436821842,574327076360, 2788765754222,13568119543636,66085999862556, 322392161536992,1574222913418742,7696752549738556, 37661385553835476,184479995723373904] |