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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 12 |
| 4 | 28 |
| 5 | 124 |
| 6 | 168 |
| 7 | 696 |
| 8 | 1254 |
| 9 | 2800 |
| 10 | 3734 |
| 11 | 9684 |
| 12 | 13282 |
| 13 | 27576 |
| 14 | 34818 |
| 15 | 51828 |
| 16 | 71660 |
| 17 | 129380 |
| 18 | 153172 |
| 19 | 254624 |
| 20 | 312716 |
| 21 | 413774 |
| 22 | 496600 |
| 23 | 767976 |
| 24 | 879284 |
| 25 | 1219286 |
| 26 | 1422992 |
| 27 | 1845842 |
| 28 | 2173556 |
| 29 | 3043292 |
| 30 | 3345884 |
| 31 | 4556174 |
| 32 | 5288806 |
| 33 | 6365966 |
| 34 | 7188082 |
| 35 | 8786288 |
| 36 | 9615066 |
[0,2,12,28,124,168,696,1254,2800,3734,9684,13282, 27576,34818,51828,71660,129380,153172,254624, 312716,413774,496600,767976,879284,1219286, 1422992,1845842,2173556,3043292,3345884,4556174, 5288806,6365966,7188082,8786288,9615066] |