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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 13 |
| 7 | 27 |
| 8 | 68 |
| 9 | 160 |
| 10 | 404 |
| 11 | 1010 |
| 12 | 2604 |
| 13 | 6726 |
| 14 | 17661 |
| 15 | 46628 |
| 16 | 124287 |
| 17 | 333162 |
| 18 | 898921 |
| 19 | 2437254 |
| 20 | 6640537 |
| 21 | 18166568 |
| 22 | 49890419 |
| 23 | 137478389 |
| 24 | 380031868 |
| 25 | 1053517588 |
| 26 | 2928246650 |
| 27 | 8158727139 |
| 28 | 22782938271 |
| 29 | 63752461474 |
| 30 | 178740014515 |
| 31 | 502026565792 |
| 32 | 1412409894224 |
[0,1,1,3,5,13,27,68,160,404,1010,2604,6726,17661, 46628,124287,333162,898921,2437254,6640537, 18166568,49890419,137478389,380031868,1053517588, 2928246650,8158727139,22782938271,63752461474, 178740014515,502026565792,1412409894224] |