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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 30 |
| 6 | 92 |
| 7 | 284 |
| 8 | 918 |
| 9 | 3005 |
| 10 | 10043 |
| 11 | 33943 |
| 12 | 116138 |
| 13 | 400862 |
| 14 | 1395228 |
| 15 | 4889389 |
| 16 | 17240482 |
| 17 | 61117789 |
| 18 | 217709832 |
| 19 | 778841527 |
| 20 | 2797066886 |
| 21 | 10080379573 |
| 22 | 36444817306 |
| 23 | 132147553180 |
| 24 | 480444008087 |
| 25 | 1751033068088 |
| 26 | 6396352141777 |
| 27 | 23414462628460 |
| 28 | 85878613308907 |
| 29 | 315556155264918 |
[1,1,2,4,11,30,92,284,918,3005,10043,33943,116138, 400862,1395228,4889389,17240482,61117789, 217709832,778841527,2797066886,10080379573, 36444817306,132147553180,480444008087, 1751033068088,6396352141777,23414462628460, 85878613308907,315556155264918] |