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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | -3 |
| 4 | 21 |
| 5 | -21 |
| 6 | -549 |
| 7 | 3933 |
| 8 | 7029 |
| 9 | -342549 |
| 10 | 2039499 |
| 11 | 21325437 |
| 12 | -479621979 |
| 13 | 1462333419 |
| 14 | 74172750651 |
| 15 | -1192395763107 |
| 16 | -3407789304171 |
| 17 | 380952336378411 |
| 18 | -4313364309242901 |
| 19 | -70292105696209923 |
| 20 | 2800422902218340421 |
| 21 | -15710895178041433941 |
| 22 | -1066174951636968019749 |
| 23 | 27502560229200724642653 |
| 24 | 89610782410072372514229 |
| 25 | -18826208456829546478535829 |
| 26 | 324641884843138083973324299 |
[1,-1,-3,21,-21,-549,3933,7029,-342549,2039499, 21325437,-479621979,1462333419,74172750651, -1192395763107,-3407789304171,380952336378411, -4313364309242901,-70292105696209923, 2800422902218340421,-15710895178041433941, -1066174951636968019749,27502560229200724642653, 89610782410072372514229, -18826208456829546478535829, 324641884843138083973324299] |