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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 30 |
| 4 | 231 |
| 5 | 1958 |
| 6 | 17977 |
| 7 | 173525 |
| 8 | 1741630 |
| 9 | 18004327 |
| 10 | 190569292 |
| 11 | 2056148051 |
| 12 | 22540654445 |
| 13 | 250438925115 |
| 14 | 2814570987591 |
| 15 | 31946390696157 |
| 16 | 365749566870782 |
| 17 | 4219388528587095 |
| 18 | 49005643635237875 |
| 19 | 572612058898037559 |
[1,1,5,30,231,1958,17977,173525,1741630,18004327, 190569292,2056148051,22540654445,250438925115, 2814570987591,31946390696157,365749566870782, 4219388528587095,49005643635237875, 572612058898037559] |