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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 35 |
| 6 | 123 |
| 7 | 462 |
| 8 | 1829 |
| 9 | 7558 |
| 10 | 32380 |
| 11 | 143102 |
| 12 | 649999 |
| 13 | 3026171 |
| 14 | 14411412 |
| 15 | 70095713 |
| 16 | 347817785 |
| 17 | 1759198500 |
| 18 | 9063638685 |
| 19 | 47545501777 |
| 20 | 253854457415 |
| 21 | 1379172691108 |
| 22 | 7623064091313 |
| 23 | 42860238300826 |
| 24 | 245098499411379 |
| 25 | 1425403070154478 |
| 26 | 8429327482836740 |
| 27 | 50681175605982771 |
[1,1,2,4,11,35,123,462,1829,7558,32380,143102, 649999,3026171,14411412,70095713,347817785, 1759198500,9063638685,47545501777,253854457415, 1379172691108,7623064091313,42860238300826, 245098499411379,1425403070154478,8429327482836740, 50681175605982771] |