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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 52 |
| 6 | 203 |
| 7 | 824 |
| 8 | 3407 |
| 9 | 14176 |
| 10 | 58954 |
| 11 | 244412 |
| 12 | 1010802 |
| 13 | 4167621 |
| 14 | 17133558 |
| 15 | 70278017 |
| 16 | 287797888 |
| 17 | 1177218237 |
| 18 | 4811244031 |
| 19 | 19651589669 |
| 20 | 80234989720 |
| 21 | 327503437323 |
| 22 | 1336574600154 |
| 23 | 5454075504109 |
| 24 | 22254465906164 |
| 25 | 90801509373219 |
| 26 | 370472833209387 |
[1,1,2,5,15,52,203,824,3407,14176,58954,244412, 1010802,4167621,17133558,70278017,287797888, 1177218237,4811244031,19651589669,80234989720, 327503437323,1336574600154,5454075504109, 22254465906164,90801509373219,370472833209387] |