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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 11 |
| 5 | 27 |
| 6 | 68 |
| 7 | 175 |
| 8 | 458 |
| 9 | 1215 |
| 10 | 3258 |
| 11 | 8815 |
| 12 | 24031 |
| 13 | 65937 |
| 14 | 181936 |
| 15 | 504473 |
| 16 | 1404879 |
| 17 | 3927495 |
| 18 | 11017802 |
| 19 | 31004871 |
| 20 | 87497297 |
| 21 | 247559933 |
| 22 | 702089528 |
| 23 | 1995483853 |
| 24 | 5682959332 |
| 25 | 16214622573 |
| 26 | 46343364290 |
| 27 | 132667706857 |
| 28 | 380358924209 |
[1,1,2,5,11,27,68,175,458,1215,3258,8815,24031, 65937,181936,504473,1404879,3927495,11017802, 31004871,87497297,247559933,702089528,1995483853, 5682959332,16214622573,46343364290,132667706857, 380358924209] |