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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 17 |
| 7 | 37 |
| 8 | 82 |
| 9 | 185 |
| 10 | 424 |
| 11 | 983 |
| 12 | 2301 |
| 13 | 5431 |
| 14 | 12913 |
| 15 | 30900 |
| 16 | 74361 |
| 17 | 179855 |
| 18 | 436974 |
| 19 | 1065985 |
| 20 | 2609993 |
| 21 | 6411730 |
| 22 | 15799090 |
| 23 | 39039031 |
| 24 | 96711591 |
| 25 | 240150955 |
| 26 | 597640140 |
| 27 | 1490309462 |
| 28 | 3723343793 |
| 29 | 9318686066 |
| 30 | 23360994967 |
| 31 | 58654055246 |
[1,1,1,2,4,8,17,37,82,185,424,983,2301,5431,12913, 30900,74361,179855,436974,1065985,2609993,6411730, 15799090,39039031,96711591,240150955,597640140, 1490309462,3723343793,9318686066,23360994967, 58654055246] |