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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 19 |
| 6 | 120 |
| 7 | 483 |
| 8 | 1500 |
| 9 | 3923 |
| 10 | 9069 |
| 11 | 19095 |
| 12 | 37356 |
| 13 | 68860 |
| 14 | 120835 |
| 15 | 203424 |
| 16 | 330525 |
| 17 | 520794 |
| 18 | 798830 |
| 19 | 1196562 |
| 20 | 1754859 |
| 21 | 2525385 |
| 22 | 3572722 |
| 23 | 4976785 |
| 24 | 6835554 |
| 25 | 9268149 |
| 26 | 12418275 |
| 27 | 16458065 |
| 28 | 21592350 |
| 29 | 28063386 |
| 30 | 36156069 |
| 31 | 46203670 |
| 32 | 58594123 |
[0,0,0,1,19,120,483,1500,3923,9069,19095,37356, 68860,120835,203424,330525,520794,798830,1196562, 1754859,2525385,3572722,4976785,6835554,9268149, 12418275,16458065,21592350,28063386,36156069, 46203670,58594123] |