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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 20 |
| 3 | 83 |
| 4 | 338 |
| 5 | 1425 |
| 6 | 6080 |
| 7 | 26249 |
| 8 | 114298 |
| 9 | 501405 |
| 10 | 2211832 |
| 11 | 9799095 |
| 12 | 43554852 |
| 13 | 194071913 |
| 14 | 866357594 |
| 15 | 3872915901 |
| 16 | 17331341902 |
| 17 | 77618369051 |
| 18 | 347815345000 |
| 19 | 1559266623743 |
| 20 | 6992481752642 |
| 21 | 31365036076887 |
| 22 | 140713926545922 |
[5,20,83,338,1425,6080,26249,114298,501405, 2211832,9799095,43554852,194071913,866357594, 3872915901,17331341902,77618369051,347815345000, 1559266623743,6992481752642,31365036076887, 140713926545922] |