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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 5 |
| 3 | 122 |
| 4 | 1022 |
| 5 | 5122 |
| 6 | 18847 |
| 7 | 56332 |
| 8 | 144924 |
| 9 | 332844 |
| 10 | 699369 |
| 11 | 1367894 |
| 12 | 2522234 |
| 13 | 4426526 |
| 14 | 7449091 |
| 15 | 12090616 |
| 16 | 19017016 |
| 17 | 29097336 |
| 18 | 43447053 |
| 19 | 63477138 |
| 20 | 90949238 |
| 21 | 128037338 |
| 22 | 177396263 |
| 23 | 242237380 |
| 24 | 326411860 |
| 25 | 434501860 |
| 26 | 571919985 |
| 27 | 745017390 |
[0,0,5,122,1022,5122,18847,56332,144924,332844, 699369,1367894,2522234,4426526,7449091,12090616, 19017016,29097336,43447053,63477138,90949238, 128037338,177396263,242237380,326411860,434501860, 571919985,745017390] |