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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 16 |
| 4 | 53 |
| 5 | 202 |
| 6 | 826 |
| 7 | 3724 |
| 8 | 17939 |
| 9 | 93390 |
| 10 | 516125 |
| 11 | 3042412 |
| 12 | 18923139 |
| 13 | 124368810 |
| 14 | 857827458 |
| 15 | 6208594458 |
| 16 | 46937360868 |
| 17 | 370335617694 |
| 18 | 3039823038753 |
| 19 | 25928519847988 |
| 20 | 229285625745624 |
| 21 | 2099543718917418 |
| 22 | 19872430464012935 |
| 23 | 194203934113959970 |
| 24 | 1956736801957704866 |
[1,2,5,16,53,202,826,3724,17939,93390,516125, 3042412,18923139,124368810,857827458,6208594458, 46937360868,370335617694,3039823038753, 25928519847988,229285625745624,2099543718917418, 19872430464012935,194203934113959970, 1956736801957704866] |