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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 11 |
| 6 | 29 |
| 7 | 76 |
| 8 | 233 |
| 9 | 685 |
| 10 | 2329 |
| 11 | 7534 |
| 12 | 27949 |
| 13 | 97943 |
| 14 | 391285 |
| 15 | 1469144 |
| 16 | 6260561 |
| 17 | 24975449 |
| 18 | 112690097 |
| 19 | 474533530 |
| 20 | 2253801941 |
| 21 | 9965204131 |
| 22 | 49583642701 |
| 23 | 229199695012 |
| 24 | 1190007424825 |
| 25 | 5729992375301 |
| 26 | 30940193045449 |
| 27 | 154709794133126 |
| 28 | 866325405272573 |
[1,1,1,2,5,11,29,76,233,685,2329,7534,27949,97943, 391285,1469144,6260561,24975449,112690097, 474533530,2253801941,9965204131,49583642701, 229199695012,1190007424825,5729992375301, 30940193045449,154709794133126,866325405272573] |