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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 33 |
| 4 | 150 |
| 5 | 687 |
| 6 | 3260 |
| 7 | 15535 |
| 8 | 75200 |
| 9 | 365065 |
| 10 | 1786315 |
| 11 | 8758688 |
| 12 | 43134180 |
| 13 | 212743678 |
| 14 | 1052015189 |
| 15 | 5207997317 |
| 16 | 25824475180 |
| 17 | 128160594114 |
| 18 | 636719791109 |
| 19 | 3165313770397 |
| 20 | 15747425122161 |
| 21 | 78381360717633 |
| 22 | 390343913148965 |
| 23 | 1944666404124979 |
| 24 | 9691986000325862 |
| 25 | 48317912738860882 |
| 26 | 240952575436395991 |
[1,2,8,33,150,687,3260,15535,75200,365065,1786315, 8758688,43134180,212743678,1052015189,5207997317, 25824475180,128160594114,636719791109, 3165313770397,15747425122161,78381360717633, 390343913148965,1944666404124979,9691986000325862, 48317912738860882,240952575436395991] |