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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 7 |
| 2 | 10 |
| 3 | 15 |
| 4 | 25 |
| 5 | 43 |
| 6 | 79 |
| 7 | 147 |
| 8 | 283 |
| 9 | 547 |
| 10 | 1075 |
| 11 | 2115 |
| 12 | 4195 |
| 13 | 8323 |
| 14 | 16579 |
| 15 | 33027 |
| 16 | 65923 |
| 17 | 131587 |
| 18 | 262915 |
| 19 | 525315 |
| 20 | 1050115 |
| 21 | 2099203 |
| 22 | 4197379 |
| 23 | 8392707 |
| 24 | 16783363 |
| 25 | 33562627 |
| 26 | 67121155 |
| 27 | 134234115 |
| 28 | 268460035 |
| 29 | 536903683 |
| 30 | 1073790979 |
[4,7,10,15,25,43,79,147,283,547,1075,2115,4195, 8323,16579,33027,65923,131587,262915,525315, 1050115,2099203,4197379,8392707,16783363,33562627, 67121155,134234115,268460035,536903683,1073790979] |