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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 5 |
| 6 | 23 |
| 7 | 82 |
| 8 | 230 |
| 9 | 560 |
| 10 | 1208 |
| 11 | 2392 |
| 12 | 4405 |
| 13 | 7673 |
| 14 | 12733 |
| 15 | 20320 |
| 16 | 31326 |
| 17 | 46914 |
| 18 | 68460 |
| 19 | 97698 |
| 20 | 136635 |
| 21 | 187737 |
| 22 | 253813 |
| 23 | 338240 |
| 24 | 444818 |
| 25 | 578038 |
| 26 | 742898 |
| 27 | 945224 |
| 28 | 1191443 |
| 29 | 1488955 |
| 30 | 1845865 |
| 31 | 2271410 |
| 32 | 2775640 |
| 33 | 3369910 |
| 34 | 4066506 |
| 35 | 4879200 |
| 36 | 5822823 |
| 37 | 6913887 |
| 38 | 8170095 |
[0,0,0,1,5,23,82,230,560,1208,2392,4405,7673, 12733,20320,31326,46914,68460,97698,136635,187737, 253813,338240,444818,578038,742898,945224,1191443, 1488955,1845865,2271410,2775640,3369910,4066506, 4879200,5822823,6913887,8170095] |