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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 9 |
| 5 | 23 |
| 6 | 56 |
| 7 | 122 |
| 8 | 323 |
| 9 | 792 |
| 10 | 2060 |
| 11 | 5199 |
| 12 | 13314 |
| 13 | 35171 |
| 14 | 94077 |
| 15 | 249285 |
| 16 | 662901 |
| 17 | 1775244 |
| 18 | 4806724 |
| 19 | 13125887 |
| 20 | 36107283 |
| 21 | 99863241 |
| 22 | 276784435 |
| 23 | 768288783 |
| 24 | 2143763275 |
| 25 | 6037486060 |
| 26 | 17171063218 |
| 27 | 49187617277 |
| 28 | 141512589597 |
| 29 | 408293870713 |
| 30 | 1181084207303 |
[1,1,2,5,9,23,56,122,323,792,2060,5199,13314, 35171,94077,249285,662901,1775244,4806724, 13125887,36107283,99863241,276784435,768288783, 2143763275,6037486060,17171063218,49187617277, 141512589597,408293870713,1181084207303] |