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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 54 |
| 3 | 4500 |
| 4 | 771750 |
| 5 | 225042300 |
| 6 | 99843767100 |
| 7 | 62673358948200 |
| 8 | 52880646612543750 |
| 9 | 57733914846094987500 |
| 10 | 79199384385873103852500 |
| 11 | 133357363417740148141455000 |
| 12 | 270426506783940730406180497500 |
| 13 | 650063718230626755784087734375000 |
| 14 | 1827886309419060919156885553671875000 |
[1,2,54,4500,771750,225042300,99843767100, 62673358948200,52880646612543750, 57733914846094987500,79199384385873103852500, 133357363417740148141455000, 270426506783940730406180497500, 650063718230626755784087734375000, 1827886309419060919156885553671875000] |