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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 55 |
| 5 | 167 |
| 6 | 799 |
| 7 | 2809 |
| 8 | 13253 |
| 9 | 50221 |
| 10 | 237145 |
| 11 | 935853 |
| 12 | 4453741 |
| 13 | 18013565 |
| 14 | 86440349 |
| 15 | 356002275 |
| 16 | 1718466879 |
| 17 | 7185616567 |
| 18 | 34812951807 |
| 19 | 147461259851 |
| 20 | 716217783119 |
| 21 | 3066285777047 |
| 22 | 14926165272107 |
| 23 | 64455736815975 |
| 24 | 314445779009951 |
| 25 | 1367574352109959 |
| 26 | 6685030856081887 |
| 27 | 29253193559386847 |
[1,1,5,11,55,167,799,2809,13253,50221,237145, 935853,4453741,18013565,86440349,356002275, 1718466879,7185616567,34812951807,147461259851, 716217783119,3066285777047,14926165272107, 64455736815975,314445779009951,1367574352109959, 6685030856081887,29253193559386847] |