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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 19 |
| 6 | 43 |
| 7 | 88 |
| 8 | 207 |
| 9 | 423 |
| 10 | 951 |
| 11 | 2094 |
| 12 | 4511 |
| 13 | 9445 |
| 14 | 22025 |
| 15 | 45172 |
| 16 | 93483 |
| 17 | 205101 |
| 18 | 435515 |
| 19 | 882322 |
| 20 | 1983637 |
| 21 | 3983429 |
| 22 | 8659805 |
| 23 | 17928712 |
| 24 | 36742421 |
| 25 | 76317521 |
| 26 | 163095069 |
| 27 | 331056988 |
| 28 | 693360803 |
| 29 | 1444266731 |
[1,2,4,9,19,43,88,207,423,951,2094,4511,9445, 22025,45172,93483,205101,435515,882322,1983637, 3983429,8659805,17928712,36742421,76317521, 163095069,331056988,693360803,1444266731] |