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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 30 |
| 5 | 185 |
| 6 | 1226 |
| 7 | 8442 |
| 8 | 60289 |
| 9 | 442089 |
| 10 | 3314203 |
| 11 | 25295011 |
| 12 | 195990980 |
| 13 | 1538069121 |
| 14 | 12203218743 |
| 15 | 97746332667 |
| 16 | 789480879664 |
| 17 | 6423539487002 |
| 18 | 52607252796831 |
| 19 | 433368610079872 |
| 20 | 3588859890833443 |
| 21 | 29862449600982149 |
| 22 | 249560820679038935 |
| 23 | 2093852201126089073 |
[1,0,1,5,30,185,1226,8442,60289,442089,3314203, 25295011,195990980,1538069121,12203218743, 97746332667,789480879664,6423539487002, 52607252796831,433368610079872,3588859890833443, 29862449600982149,249560820679038935, 2093852201126089073] |