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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 16 |
| 3 | 37 |
| 4 | 164 |
| 5 | 365 |
| 6 | 1259 |
| 7 | 6660 |
| 8 | 387539 |
| 9 | 1944355 |
| 10 | 6220604 |
| 11 | 14385563 |
| 12 | 63762856 |
| 13 | 141911275 |
| 14 | 489496681 |
| 15 | 2589394680 |
| 16 | 150674388121 |
| 17 | 755961335285 |
| 18 | 2418558393976 |
| 19 | 5593078123237 |
| 20 | 24790870886924 |
| 21 | 55174819897085 |
| 22 | 190315330578179 |
| 23 | 1006751472787980 |
[1,5,16,37,164,365,1259,6660,387539,1944355, 6220604,14385563,63762856,141911275,489496681, 2589394680,150674388121,755961335285, 2418558393976,5593078123237,24790870886924, 55174819897085,190315330578179,1006751472787980] |