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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 5 |
| 7 | 7 |
| 8 | 23 |
| 9 | 48 |
| 10 | 190 |
| 11 | 469 |
| 12 | 2076 |
| 13 | 5613 |
| 14 | 27112 |
| 15 | 80004 |
| 16 | 415821 |
| 17 | 1332560 |
| 18 | 7380671 |
| 19 | 25483465 |
| 20 | 149401274 |
| 21 | 552137511 |
| 22 | 3408722899 |
| 23 | 13414205244 |
| 24 | 86845091349 |
| 25 | 362317409552 |
| 26 | 2451291749604 |
| 27 | 10800354549538 |
| 28 | 76134098052646 |
| 29 | 353054546986058 |
| 30 | 2586405677507199 |
[1,1,1,1,2,2,5,7,23,48,190,469,2076,5613,27112, 80004,415821,1332560,7380671,25483465,149401274, 552137511,3408722899,13414205244,86845091349, 362317409552,2451291749604,10800354549538, 76134098052646,353054546986058,2586405677507199] |