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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 11 |
| 5 | 37 |
| 6 | 71 |
| 7 | 201 |
| 8 | 352 |
| 9 | 887 |
| 10 | 3015 |
| 11 | 4802 |
| 12 | 14552 |
| 13 | 30366 |
| 14 | 45326 |
| 15 | 90316 |
| 16 | 234343 |
| 17 | 582691 |
| 18 | 819205 |
| 19 | 1938560 |
| 20 | 3449498 |
| 21 | 4698053 |
| 22 | 10457616 |
| 23 | 17852459 |
| 24 | 38120211 |
| 25 | 99889551 |
| 26 | 163116820 |
| 27 | 211767528 |
| 28 | 340543921 |
| 29 | 437493270 |
| 30 | 693911423 |
[1,2,5,11,37,71,201,352,887,3015,4802,14552,30366, 45326,90316,234343,582691,819205,1938560,3449498, 4698053,10457616,17852459,38120211,99889551, 163116820,211767528,340543921,437493270,693911423] |