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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 1 |
| 5 | 521 |
| 6 | 1261 |
| 7 | 102943 |
| 8 | 1 |
| 9 | 38742049 |
| 10 | 99009901 |
| 11 | 23775972551 |
| 12 | 429960961 |
| 13 | 21633936185161 |
| 14 | 56406126018061 |
| 15 | 27368368148803711 |
| 16 | 1 |
| 17 | 45957792327018709121 |
| 18 | 121065871000912423309 |
| 19 | 98920982783015679456199 |
[1,1,7,1,521,1261,102943,1,38742049,99009901, 23775972551,429960961,21633936185161, 56406126018061,27368368148803711,1, 45957792327018709121,121065871000912423309, 98920982783015679456199] |