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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 17 |
| 4 | 34 |
| 5 | 92 |
| 6 | 223 |
| 7 | 700 |
| 8 | 1747 |
| 9 | 4931 |
| 10 | 12767 |
| 11 | 35978 |
| 12 | 94910 |
| 13 | 262007 |
| 14 | 698588 |
| 15 | 1916541 |
| 16 | 5144619 |
| 17 | 14035991 |
| 18 | 37816996 |
| 19 | 102894248 |
| 20 | 277866327 |
| 21 | 754687018 |
| 22 | 2040711739 |
| 23 | 5537019209 |
| 24 | 14984261865 |
| 25 | 40631762944 |
| 26 | 110008357730 |
| 27 | 298195807995 |
[1,3,17,34,92,223,700,1747,4931,12767,35978,94910, 262007,698588,1916541,5144619,14035991,37816996, 102894248,277866327,754687018,2040711739, 5537019209,14984261865,40631762944,110008357730, 298195807995] |