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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1025 |
| 4 | 59050 |
| 5 | 1108650 |
| 6 | 10815226 |
| 7 | 71340451 |
| 8 | 352767124 |
| 9 | 1427557524 |
| 10 | 4904576300 |
| 11 | 14914341925 |
| 12 | 40791300350 |
| 13 | 102769130750 |
| 14 | 240345147350 |
| 15 | 529882277575 |
| 16 | 1105458926376 |
| 17 | 2206044295976 |
| 18 | 4218551412024 |
| 19 | 7792505423049 |
| 20 | 13913571680850 |
| 21 | 24163571680850 |
| 22 | 40817515234450 |
[0,0,1025,59050,1108650,10815226,71340451, 352767124,1427557524,4904576300,14914341925, 40791300350,102769130750,240345147350, 529882277575,1105458926376,2206044295976, 4218551412024,7792505423049,13913571680850, 24163571680850,40817515234450] |