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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 16 |
| 5 | 43 |
| 6 | 106 |
| 7 | 247 |
| 8 | 554 |
| 9 | 1199 |
| 10 | 2520 |
| 11 | 5147 |
| 12 | 10256 |
| 13 | 19964 |
| 14 | 38071 |
| 15 | 71226 |
| 16 | 130996 |
| 17 | 237132 |
| 18 | 423118 |
| 19 | 744903 |
| 20 | 1295274 |
| 21 | 2226315 |
| 22 | 3785452 |
| 23 | 6371304 |
| 24 | 10621516 |
| 25 | 17547538 |
| 26 | 28743111 |
| 27 | 46701014 |
| 28 | 75296105 |
| 29 | 120512148 |
| 30 | 191536534 |
| 31 | 302392119 |
| 32 | 474368206 |
[0,1,5,16,43,106,247,554,1199,2520,5147,10256, 19964,38071,71226,130996,237132,423118,744903, 1295274,2226315,3785452,6371304,10621516,17547538, 28743111,46701014,75296105,120512148,191536534, 302392119,474368206] |