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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 7 |
| 3 | 10 |
| 4 | 18 |
| 5 | 28 |
| 6 | 56 |
| 7 | 98 |
| 8 | 208 |
| 9 | 418 |
| 10 | 933 |
| 11 | 2044 |
| 12 | 4777 |
| 13 | 11072 |
| 14 | 26548 |
| 15 | 63672 |
| 16 | 155248 |
| 17 | 379348 |
| 18 | 935278 |
| 19 | 2311294 |
| 20 | 5741228 |
| 21 | 14292966 |
| 22 | 35699049 |
| 23 | 89339860 |
| 24 | 224097602 |
| 25 | 563074848 |
| 26 | 1417313897 |
| 27 | 3572747650 |
| 28 | 9019154944 |
| 29 | 22797181996 |
| 30 | 57693378135 |
| 31 | 146168107034 |
| 32 | 370712004868 |
[4,7,10,18,28,56,98,208,418,933,2044,4777,11072, 26548,63672,155248,379348,935278,2311294,5741228, 14292966,35699049,89339860,224097602,563074848, 1417313897,3572747650,9019154944,22797181996, 57693378135,146168107034,370712004868] |