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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 19 |
| 6 | 42 |
| 7 | 93 |
| 8 | 205 |
| 9 | 453 |
| 10 | 1003 |
| 11 | 2221 |
| 12 | 4918 |
| 13 | 10892 |
| 14 | 24126 |
| 15 | 53442 |
| 16 | 118384 |
| 17 | 262248 |
| 18 | 580946 |
| 19 | 1286953 |
| 20 | 2850965 |
| 21 | 6315712 |
| 22 | 13991153 |
| 23 | 30994539 |
| 24 | 68662111 |
| 25 | 152107038 |
| 26 | 336962513 |
| 27 | 746472721 |
| 28 | 1653660451 |
| 29 | 3663352982 |
| 30 | 8115423952 |
| 31 | 17978094917 |
[1,1,2,4,9,19,42,93,205,453,1003,2221,4918,10892, 24126,53442,118384,262248,580946,1286953,2850965, 6315712,13991153,30994539,68662111,152107038, 336962513,746472721,1653660451,3663352982, 8115423952,17978094917] |