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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 4 |
| 5 | 4 |
| 6 | 9 |
| 7 | 12 |
| 8 | 27 |
| 9 | 49 |
| 10 | 111 |
| 11 | 236 |
| 12 | 562 |
| 13 | 1302 |
| 14 | 3172 |
| 15 | 7746 |
| 16 | 19347 |
| 17 | 48630 |
| 18 | 123923 |
| 19 | 317956 |
| 20 | 823178 |
| 21 | 2144518 |
| 22 | 5623993 |
| 23 | 14828075 |
| 24 | 39300482 |
| 25 | 104636894 |
| 26 | 279794753 |
| 27 | 751065509 |
| 28 | 2023446206 |
| 29 | 5469566586 |
| 30 | 14830879661 |
| 31 | 40330829031 |
| 32 | 109972429568 |
| 33 | 300628862717 |
[1,1,2,2,4,4,9,12,27,49,111,236,562,1302,3172, 7746,19347,48630,123923,317956,823178,2144518, 5623993,14828075,39300482,104636894,279794753, 751065509,2023446206,5469566586,14830879661, 40330829031,109972429568,300628862717] |