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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 60 |
| 4 | 264 |
| 5 | 930 |
| 6 | 2766 |
| 7 | 7205 |
| 8 | 16880 |
| 9 | 36279 |
| 10 | 72610 |
| 11 | 136906 |
| 12 | 245400 |
| 13 | 421200 |
| 14 | 696294 |
| 15 | 1113915 |
| 16 | 1731296 |
| 17 | 2622845 |
| 18 | 3883770 |
| 19 | 5634184 |
| 20 | 8023720 |
| 21 | 11236686 |
| 22 | 15497790 |
| 23 | 21078465 |
| 24 | 28303824 |
| 25 | 37560275 |
| 26 | 49303826 |
| 27 | 64069110 |
| 28 | 82479160 |
| 29 | 105255964 |
| 30 | 133231830 |
| 31 | 167361591 |
| 32 | 208735680 |
[1,10,60,264,930,2766,7205,16880,36279,72610, 136906,245400,421200,696294,1113915,1731296, 2622845,3883770,5634184,8023720,11236686,15497790, 21078465,28303824,37560275,49303826,64069110, 82479160,105255964,133231830,167361591,208735680] |