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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 44 |
| 4 | 232 |
| 5 | 1253 |
| 6 | 6895 |
| 7 | 38376 |
| 8 | 215396 |
| 9 | 1217109 |
| 10 | 6914696 |
| 11 | 39458777 |
| 12 | 226006814 |
| 13 | 1298557455 |
| 14 | 7481167001 |
| 15 | 43200760775 |
| 16 | 249977853797 |
| 17 | 1449092483085 |
| 18 | 8413731049376 |
| 19 | 48922225054030 |
| 20 | 284830701327470 |
| 21 | 1660264158620798 |
| 22 | 9687938318036091 |
| 23 | 56586034949700662 |
[1,1,8,44,232,1253,6895,38376,215396,1217109, 6914696,39458777,226006814,1298557455,7481167001, 43200760775,249977853797,1449092483085, 8413731049376,48922225054030,284830701327470, 1660264158620798,9687938318036091, 56586034949700662] |