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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 50 |
| 4 | 286 |
| 5 | 1566 |
| 6 | 8358 |
| 7 | 43870 |
| 8 | 227606 |
| 9 | 1170926 |
| 10 | 5985958 |
| 11 | 30454590 |
| 12 | 154371126 |
| 13 | 780246286 |
| 14 | 3934789958 |
| 15 | 19808175710 |
| 16 | 99577765846 |
| 17 | 500036345646 |
| 18 | 2508771728358 |
| 19 | 12578218511230 |
| 20 | 63028531771766 |
| 21 | 315692415197006 |
| 22 | 1580661100289158 |
| 23 | 7912101596565150 |
| 24 | 39595692359108886 |
[0,1,8,50,286,1566,8358,43870,227606,1170926, 5985958,30454590,154371126,780246286,3934789958, 19808175710,99577765846,500036345646, 2508771728358,12578218511230,63028531771766, 315692415197006,1580661100289158,7912101596565150, 39595692359108886] |