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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 15 |
| 4 | 44 |
| 5 | 125 |
| 6 | 347 |
| 7 | 948 |
| 8 | 2561 |
| 9 | 6863 |
| 10 | 18284 |
| 11 | 48501 |
| 12 | 128243 |
| 13 | 338276 |
| 14 | 890681 |
| 15 | 2341959 |
| 16 | 6151580 |
| 17 | 16145549 |
| 18 | 42350603 |
| 19 | 111037332 |
| 20 | 291023537 |
| 21 | 762557567 |
| 22 | 1997697740 |
| 23 | 5232632805 |
| 24 | 13704394979 |
| 25 | 35888940740 |
| 26 | 93979204457 |
| 27 | 246082227063 |
| 28 | 644334585596 |
| 29 | 1687055747453 |
[1,2,5,15,44,125,347,948,2561,6863,18284,48501, 128243,338276,890681,2341959,6151580,16145549, 42350603,111037332,291023537,762557567,1997697740, 5232632805,13704394979,35888940740,93979204457, 246082227063,644334585596,1687055747453] |