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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 27 |
| 3 | 157 |
| 4 | 979 |
| 5 | 6517 |
| 6 | 46107 |
| 7 | 345261 |
| 8 | 2726243 |
| 9 | 22623525 |
| 10 | 196712171 |
| 11 | 1787356765 |
| 12 | 16929897395 |
| 13 | 166808851541 |
| 14 | 1706299041211 |
| 15 | 18088031239437 |
| 16 | 198392625389315 |
| 17 | 2248104026019461 |
| 18 | 26283054263021963 |
| 19 | 316637825898555069 |
| 20 | 3926250785070282579 |
| 21 | 50056384077880370101 |
[1,5,27,157,979,6517,46107,345261,2726243, 22623525,196712171,1787356765,16929897395, 166808851541,1706299041211,18088031239437, 198392625389315,2248104026019461, 26283054263021963,316637825898555069, 3926250785070282579,50056384077880370101] |