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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 42 |
| 3 | 150 |
| 4 | 554 |
| 5 | 2072 |
| 6 | 7808 |
| 7 | 29536 |
| 8 | 111878 |
| 9 | 423969 |
| 10 | 1607058 |
| 11 | 6092367 |
| 12 | 23097242 |
| 13 | 87566957 |
| 14 | 331989206 |
| 15 | 1258663594 |
| 16 | 4771951574 |
| 17 | 18091832688 |
| 18 | 68591328768 |
| 19 | 260049450816 |
| 20 | 985922294306 |
| 21 | 3737915147525 |
| 22 | 14171512153838 |
| 23 | 53728281674119 |
[13,42,150,554,2072,7808,29536,111878,423969, 1607058,6092367,23097242,87566957,331989206, 1258663594,4771951574,18091832688,68591328768, 260049450816,985922294306,3737915147525, 14171512153838,53728281674119] |