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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 19 |
| 4 | 44 |
| 5 | 102 |
| 6 | 237 |
| 7 | 551 |
| 8 | 1281 |
| 9 | 2978 |
| 10 | 6923 |
| 11 | 16094 |
| 12 | 37414 |
| 13 | 86977 |
| 14 | 202197 |
| 15 | 470051 |
| 16 | 1092736 |
| 17 | 2540303 |
| 18 | 5905488 |
| 19 | 13728594 |
| 20 | 31915109 |
| 21 | 74193627 |
| 22 | 172479257 |
| 23 | 400965626 |
| 24 | 932131991 |
| 25 | 2166943978 |
| 26 | 5037533578 |
| 27 | 11710844769 |
| 28 | 27224411129 |
| 29 | 63289077427 |
[1,3,8,19,44,102,237,551,1281,2978,6923,16094, 37414,86977,202197,470051,1092736,2540303,5905488, 13728594,31915109,74193627,172479257,400965626, 932131991,2166943978,5037533578,11710844769, 27224411129,63289077427] |