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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 10 |
| 5 | 19 |
| 6 | 37 |
| 7 | 74 |
| 8 | 140 |
| 9 | 269 |
| 10 | 520 |
| 11 | 1026 |
| 12 | 1984 |
| 13 | 3831 |
| 14 | 7368 |
| 15 | 14302 |
| 16 | 27707 |
| 17 | 53729 |
| 18 | 103826 |
| 19 | 201035 |
| 20 | 389094 |
| 21 | 753858 |
| 22 | 1458852 |
| 23 | 2824336 |
| 24 | 5466167 |
| 25 | 10584567 |
| 26 | 20489682 |
| 27 | 39669401 |
| 28 | 76787404 |
| 29 | 148660956 |
| 30 | 287786132 |
| 31 | 557153147 |
| 32 | 1078562051 |
| 33 | 2088027468 |
[1,1,3,6,10,19,37,74,140,269,520,1026,1984,3831, 7368,14302,27707,53729,103826,201035,389094, 753858,1458852,2824336,5466167,10584567,20489682, 39669401,76787404,148660956,287786132,557153147, 1078562051,2088027468] |