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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 7 |
| 3 | 28 |
| 4 | 84 |
| 5 | 211 |
| 6 | 470 |
| 7 | 960 |
| 8 | 1836 |
| 9 | 3334 |
| 10 | 5806 |
| 11 | 9769 |
| 12 | 15973 |
| 13 | 25495 |
| 14 | 39869 |
| 15 | 61266 |
| 16 | 92743 |
| 17 | 138587 |
| 18 | 204790 |
| 19 | 299705 |
| 20 | 434952 |
| 21 | 626669 |
| 22 | 897239 |
| 23 | 1277674 |
| 24 | 1810906 |
| 25 | 2556330 |
| 26 | 3596075 |
| 27 | 5043660 |
| 28 | 7055942 |
| 29 | 9849608 |
| 30 | 13723939 |
| 31 | 19092231 |
| 32 | 26525165 |
[0,1,7,28,84,211,470,960,1836,3334,5806,9769, 15973,25495,39869,61266,92743,138587,204790, 299705,434952,626669,897239,1277674,1810906, 2556330,3596075,5043660,7055942,9849608,13723939, 19092231,26525165] |