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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 63 |
| 5 | 259 |
| 6 | 1067 |
| 7 | 4457 |
| 8 | 19191 |
| 9 | 82841 |
| 10 | 362233 |
| 11 | 1598323 |
| 12 | 7088617 |
| 13 | 31667685 |
| 14 | 142110015 |
| 15 | 640483695 |
| 16 | 2899395681 |
| 17 | 13163953953 |
| 18 | 59965256157 |
| 19 | 273940539817 |
| 20 | 1254326068887 |
| 21 | 5757231255235 |
| 22 | 26479800661155 |
| 23 | 122016618174329 |
| 24 | 563255251234927 |
| 25 | 2604287666051211 |
| 26 | 12059299339779457 |
| 27 | 55919399667456419 |
[1,1,5,17,63,259,1067,4457,19191,82841,362233, 1598323,7088617,31667685,142110015,640483695, 2899395681,13163953953,59965256157,273940539817, 1254326068887,5757231255235,26479800661155, 122016618174329,563255251234927,2604287666051211, 12059299339779457,55919399667456419] |