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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 59 |
| 5 | 214 |
| 6 | 833 |
| 7 | 3348 |
| 8 | 13757 |
| 9 | 57614 |
| 10 | 245029 |
| 11 | 1057097 |
| 12 | 4612119 |
| 13 | 20312134 |
| 14 | 90203785 |
| 15 | 403479671 |
| 16 | 1816531091 |
| 17 | 8225525396 |
| 18 | 37436630399 |
| 19 | 171169846195 |
| 20 | 785894026193 |
| 21 | 3622052052200 |
| 22 | 16751645552171 |
| 23 | 77721558215220 |
| 24 | 361656525135493 |
| 25 | 1687428217822128 |
| 26 | 7893052613443195 |
| 27 | 37006573241509619 |
[1,2,5,17,59,214,833,3348,13757,57614,245029, 1057097,4612119,20312134,90203785,403479671, 1816531091,8225525396,37436630399,171169846195, 785894026193,3622052052200,16751645552171, 77721558215220,361656525135493,1687428217822128, 7893052613443195,37006573241509619] |