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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 59 |
| 5 | 239 |
| 6 | 995 |
| 7 | 3967 |
| 8 | 16685 |
| 9 | 72029 |
| 10 | 308013 |
| 11 | 1326509 |
| 12 | 5839973 |
| 13 | 25751313 |
| 14 | 113486965 |
| 15 | 505253549 |
| 16 | 2264923651 |
| 17 | 10149497751 |
| 18 | 45647471491 |
| 19 | 206545814791 |
| 20 | 936339133515 |
| 21 | 4249377202291 |
| 22 | 19357161132847 |
| 23 | 88430112102083 |
| 24 | 404359447342391 |
| 25 | 1852486534010095 |
| 26 | 8508801394789043 |
| 27 | 39136469862569959 |
[1,1,5,17,59,239,995,3967,16685,72029,308013, 1326509,5839973,25751313,113486965,505253549, 2264923651,10149497751,45647471491,206545814791, 936339133515,4249377202291,19357161132847, 88430112102083,404359447342391,1852486534010095, 8508801394789043,39136469862569959] |