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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 6 |
| 3 | 13 |
| 4 | 27 |
| 5 | 54 |
| 6 | 109 |
| 7 | 218 |
| 8 | 437 |
| 9 | 874 |
| 10 | 1749 |
| 11 | 3499 |
| 12 | 6998 |
| 13 | 13997 |
| 14 | 27994 |
| 15 | 55989 |
| 16 | 111978 |
| 17 | 223957 |
| 18 | 447915 |
| 19 | 895830 |
| 20 | 1791661 |
| 21 | 3583322 |
| 22 | 7166645 |
| 23 | 14333290 |
| 24 | 28666581 |
| 25 | 57333163 |
| 26 | 114666326 |
| 27 | 229332653 |
| 28 | 458665307 |
| 29 | 917330614 |
| 30 | 1834661229 |
| 31 | 3669322459 |
[1,3,6,13,27,54,109,218,437,874,1749,3499,6998, 13997,27994,55989,111978,223957,447915,895830, 1791661,3583322,7166645,14333290,28666581, 57333163,114666326,229332653,458665307,917330614, 1834661229,3669322459] |