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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 27 |
| 4 | 114 |
| 5 | 523 |
| 6 | 2589 |
| 7 | 13744 |
| 8 | 77821 |
| 9 | 467767 |
| 10 | 2972432 |
| 11 | 19895813 |
| 12 | 139824045 |
| 13 | 1028804338 |
| 14 | 7905124379 |
| 15 | 63287544055 |
| 16 | 526827208698 |
| 17 | 4551453462543 |
| 18 | 40740750631417 |
| 19 | 377254241891064 |
| 20 | 3608700264369193 |
| 21 | 35613444194346451 |
| 22 | 362161573323083920 |
| 23 | 3790824599495473121 |
[1,2,7,27,114,523,2589,13744,77821,467767,2972432, 19895813,139824045,1028804338,7905124379, 63287544055,526827208698,4551453462543, 40740750631417,377254241891064,3608700264369193, 35613444194346451,362161573323083920, 3790824599495473121] |