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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 47 |
| 5 | 159 |
| 6 | 574 |
| 7 | 2109 |
| 8 | 8169 |
| 9 | 31723 |
| 10 | 126215 |
| 11 | 509507 |
| 12 | 2092740 |
| 13 | 8635109 |
| 14 | 36085069 |
| 15 | 152237219 |
| 16 | 646761004 |
| 17 | 2761600479 |
| 18 | 11884514477 |
| 19 | 51431756012 |
| 20 | 223469531806 |
| 21 | 975384346075 |
| 22 | 4278644887877 |
| 23 | 18833199190484 |
| 24 | 83153244001660 |
| 25 | 368482889987396 |
| 26 | 1638176509148827 |
| 27 | 7300576114116047 |
[1,2,5,14,47,159,574,2109,8169,31723,126215, 509507,2092740,8635109,36085069,152237219, 646761004,2761600479,11884514477,51431756012, 223469531806,975384346075,4278644887877, 18833199190484,83153244001660,368482889987396, 1638176509148827,7300576114116047] |