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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 22 |
| 4 | 86 |
| 5 | 340 |
| 6 | 1403 |
| 7 | 5912 |
| 8 | 25255 |
| 9 | 109518 |
| 10 | 478944 |
| 11 | 2112598 |
| 12 | 9392174 |
| 13 | 41972854 |
| 14 | 188575186 |
| 15 | 851123779 |
| 16 | 3855663703 |
| 17 | 17529454105 |
| 18 | 79937906002 |
| 19 | 365518321803 |
| 20 | 1675610232396 |
| 21 | 7698292434046 |
| 22 | 35440859672787 |
| 23 | 163468742882547 |
| 24 | 755269073235057 |
| 25 | 3495106155974599 |
| 26 | 16197749380386370 |
| 27 | 75168376975945930 |
[1,2,6,22,86,340,1403,5912,25255,109518,478944, 2112598,9392174,41972854,188575186,851123779, 3855663703,17529454105,79937906002,365518321803, 1675610232396,7698292434046,35440859672787, 163468742882547,755269073235057,3495106155974599, 16197749380386370,75168376975945930] |