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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 13 |
| 6 | 36 |
| 7 | 103 |
| 8 | 306 |
| 9 | 930 |
| 10 | 2887 |
| 11 | 9100 |
| 12 | 29082 |
| 13 | 93951 |
| 14 | 306414 |
| 15 | 1007361 |
| 16 | 3335088 |
| 17 | 11108986 |
| 18 | 37203873 |
| 19 | 125193694 |
| 20 | 423099557 |
| 21 | 1435427202 |
| 22 | 4886975378 |
| 23 | 16690971648 |
| 24 | 57172387872 |
| 25 | 196358421066 |
| 26 | 676050576441 |
| 27 | 2332887221847 |
| 28 | 8067160995797 |
| 29 | 27950871439353 |
| 30 | 97019613539949 |
[1,1,2,5,13,36,103,306,930,2887,9100,29082,93951, 306414,1007361,3335088,11108986,37203873, 125193694,423099557,1435427202,4886975378, 16690971648,57172387872,196358421066,676050576441, 2332887221847,8067160995797,27950871439353, 97019613539949] |