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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 45 |
| 5 | 162 |
| 6 | 641 |
| 7 | 2718 |
| 8 | 12249 |
| 9 | 58370 |
| 10 | 294493 |
| 11 | 1571374 |
| 12 | 8858053 |
| 13 | 52542882 |
| 14 | 326804185 |
| 15 | 2122860862 |
| 16 | 14366452913 |
| 17 | 101063123202 |
| 18 | 738075208501 |
| 19 | 5587492946510 |
| 20 | 43795838894941 |
| 21 | 354876969914786 |
| 22 | 2968890716640945 |
[1,2,5,14,45,162,641,2718,12249,58370,294493, 1571374,8858053,52542882,326804185,2122860862, 14366452913,101063123202,738075208501, 5587492946510,43795838894941,354876969914786, 2968890716640945] |