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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 6 |
| 6 | 11 |
| 7 | 28 |
| 8 | 51 |
| 9 | 242 |
| 10 | 532 |
| 11 | 1545 |
| 12 | 6188 |
| 13 | 16592 |
| 14 | 86940 |
| 15 | 302909 |
| 16 | 967523 |
| 17 | 3808673 |
| 18 | 23029861 |
| 19 | 71772352 |
| 20 | 484629531 |
| 21 | 1840886853 |
| 22 | 9376324526 |
| 23 | 37878035106 |
| 24 | 204542429832 |
| 25 | 1458360522892 |
| 26 | 6241489795503 |
| 27 | 45783932444672 |
| 28 | 211848342780210 |
| 29 | 1137580874772724 |
[1,1,1,2,2,6,11,28,51,242,532,1545,6188,16592, 86940,302909,967523,3808673,23029861,71772352, 484629531,1840886853,9376324526,37878035106, 204542429832,1458360522892,6241489795503, 45783932444672,211848342780210,1137580874772724] |