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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 26 |
| 4 | 163 |
| 5 | 1116 |
| 6 | 8103 |
| 7 | 61271 |
| 8 | 477333 |
| 9 | 3804635 |
| 10 | 30878286 |
| 11 | 254306304 |
| 12 | 2119951278 |
| 13 | 17853490116 |
| 14 | 151669244490 |
| 15 | 1298170716509 |
| 16 | 11184287356123 |
| 17 | 96913643138408 |
| 18 | 844068755391993 |
| 19 | 7384974708096903 |
| 20 | 64877915485235577 |
| 21 | 572070036121210437 |
| 22 | 5061247928589279937 |
[1,1,5,26,163,1116,8103,61271,477333,3804635, 30878286,254306304,2119951278,17853490116, 151669244490,1298170716509,11184287356123, 96913643138408,844068755391993,7384974708096903, 64877915485235577,572070036121210437, 5061247928589279937] |