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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 7 |
| 7 | 14 |
| 8 | 42 |
| 9 | 213 |
| 10 | 2837 |
| 11 | 175450 |
| 12 | 139759600 |
| 13 | 6837625106787 |
| 14 | 266437144916648607844 |
| 15 | 508009471379488821444261986503540 |
| 16 | 37745517525533091954736701257541238885239740313139682 |
| 17 | 5347426383812697233786139576220450142250373277499130252554080838158299886992660750432 |
[1,2,2,3,4,7,14,42,213,2837,175450,139759600, 6837625106787,266437144916648607844, 508009471379488821444261986503540, 37745517525533091954736701257541238885239740313139\ 682, 53474263838126972337861395762204501422503732774991\ 30252554080838158299886992660750432] |