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| n | a(n) |
|---|---|
| 1 | 2540 |
| 2 | 7212 |
| 3 | 26370 |
| 4 | 98002 |
| 5 | 279743 |
| 6 | 774662 |
| 7 | 2035893 |
| 8 | 5114873 |
| 9 | 12474341 |
| 10 | 29590558 |
| 11 | 68901604 |
| 12 | 158137068 |
| 13 | 357684484 |
| 14 | 800611865 |
| 15 | 1776191086 |
| 16 | 3909310915 |
| 17 | 8548743880 |
| 18 | 18587419029 |
| 19 | 40212191986 |
| 20 | 86599353650 |
| 21 | 185779037285 |
| 22 | 397204639125 |
[2540,7212,26370,98002,279743,774662,2035893, 5114873,12474341,29590558,68901604,158137068, 357684484,800611865,1776191086,3909310915, 8548743880,18587419029,40212191986,86599353650, 185779037285,397204639125] |