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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 5 |
| 7 | 6 |
| 8 | 18 |
| 9 | 25 |
| 10 | 63 |
| 11 | 90 |
| 12 | 202 |
| 13 | 301 |
| 14 | 650 |
| 15 | 965 |
| 16 | 2016 |
| 17 | 3025 |
| 18 | 6220 |
| 19 | 9330 |
| 20 | 18970 |
| 21 | 28495 |
| 22 | 57650 |
| 23 | 86526 |
| 24 | 174210 |
| 25 | 261624 |
| 26 | 525693 |
| 27 | 788945 |
| 28 | 1582462 |
| 29 | 2375101 |
| 30 | 4759482 |
| 31 | 7141686 |
| 32 | 14300976 |
| 33 | 21457735 |
| 34 | 42951825 |
| 35 | 64439003 |
| 36 | 128946888 |
| 37 | 193448101 |
| 38 | 387037370 |
| 39 | 580606145 |
| 40 | 1161485370 |
[0,0,0,1,1,5,6,18,25,63,90,202,301,650,965,2016, 3025,6220,9330,18970,28495,57650,86526,174210, 261624,525693,788945,1582462,2375101,4759482, 7141686,14300976,21457735,42951825,64439003, 128946888,193448101,387037370,580606145, 1161485370] |