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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 5 |
| 4 | 15 |
| 5 | 22 |
| 6 | 59 |
| 7 | 90 |
| 8 | 230 |
| 9 | 362 |
| 10 | 902 |
| 11 | 1450 |
| 12 | 3551 |
| 13 | 5802 |
| 14 | 14022 |
| 15 | 23210 |
| 16 | 55492 |
| 17 | 92842 |
| 18 | 219974 |
| 19 | 371370 |
| 20 | 873101 |
| 21 | 1485482 |
| 22 | 3468893 |
| 23 | 5941930 |
| 24 | 13793183 |
| 25 | 23767722 |
| 26 | 54880915 |
| 27 | 95070890 |
| 28 | 218480607 |
| 29 | 380283562 |
| 30 | 870164852 |
| 31 | 1521134250 |
[1,1,4,5,15,22,59,90,230,362,902,1450,3551,5802, 14022,23210,55492,92842,219974,371370,873101, 1485482,3468893,5941930,13793183,23767722, 54880915,95070890,218480607,380283562,870164852, 1521134250] |