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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 13 |
| 5 | 34 |
| 6 | 81 |
| 7 | 175 |
| 8 | 403 |
| 9 | 890 |
| 10 | 1977 |
| 11 | 4262 |
| 12 | 9356 |
| 13 | 19963 |
| 14 | 42573 |
| 15 | 90865 |
| 16 | 191206 |
| 17 | 401803 |
| 18 | 837898 |
| 19 | 1744231 |
| 20 | 3607504 |
| 21 | 7436628 |
| 22 | 15254309 |
| 23 | 31185686 |
| 24 | 63552725 |
| 25 | 128963236 |
| 26 | 260933000 |
| 27 | 526140540 |
| 28 | 1057927323 |
| 29 | 2120500885 |
| 30 | 4239012067 |
| 31 | 8449746787 |
| 32 | 16799938614 |
[1,1,2,7,13,34,81,175,403,890,1977,4262,9356, 19963,42573,90865,191206,401803,837898,1744231, 3607504,7436628,15254309,31185686,63552725, 128963236,260933000,526140540,1057927323, 2120500885,4239012067,8449746787,16799938614] |