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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 36 |
| 4 | 156 |
| 5 | 708 |
| 6 | 3242 |
| 7 | 15036 |
| 8 | 70667 |
| 9 | 334535 |
| 10 | 1591110 |
| 11 | 7611704 |
| 12 | 36559791 |
| 13 | 176122332 |
| 14 | 850932300 |
| 15 | 4121606328 |
| 16 | 20003197132 |
| 17 | 97256045912 |
| 18 | 473643889965 |
| 19 | 2309916896835 |
| 20 | 11279389351186 |
| 21 | 55141375665780 |
| 22 | 269847701530637 |
| 23 | 1321793829895010 |
| 24 | 6480105030164733 |
| 25 | 31793812875932030 |
| 26 | 156104594940769207 |
[1,2,9,36,156,708,3242,15036,70667,334535,1591110, 7611704,36559791,176122332,850932300,4121606328, 20003197132,97256045912,473643889965, 2309916896835,11279389351186,55141375665780, 269847701530637,1321793829895010,6480105030164733, 31793812875932030,156104594940769207] |