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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 12 |
| 6 | 34 |
| 7 | 112 |
| 8 | 340 |
| 9 | 1073 |
| 10 | 3335 |
| 11 | 10487 |
| 12 | 32890 |
| 13 | 103628 |
| 14 | 326677 |
| 15 | 1032139 |
| 16 | 3264645 |
| 17 | 10341541 |
| 18 | 32795480 |
| 19 | 104121342 |
| 20 | 330894709 |
| 21 | 1052560143 |
| 22 | 3350969989 |
| 23 | 10676723143 |
| 24 | 34042525681 |
| 25 | 108617828200 |
| 26 | 346780908546 |
| 27 | 1107812557123 |
[0,1,2,4,12,34,112,340,1073,3335,10487,32890, 103628,326677,1032139,3264645,10341541,32795480, 104121342,330894709,1052560143,3350969989, 10676723143,34042525681,108617828200,346780908546, 1107812557123] |