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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 13 |
| 4 | 17 |
| 5 | 489 |
| 6 | 506 |
| 7 | 2007 |
| 8 | 6527 |
| 9 | 8534 |
| 10 | 245479 |
| 11 | 254013 |
| 12 | 1007518 |
| 13 | 3276567 |
| 14 | 4284085 |
| 15 | 123230947 |
| 16 | 127515032 |
| 17 | 505776043 |
| 18 | 1644843161 |
| 19 | 2150619204 |
| 20 | 61862180873 |
| 21 | 64012800077 |
| 22 | 253900581104 |
| 23 | 825714543389 |
| 24 | 1079615124493 |
| 25 | 31054938029193 |
| 26 | 32134553153686 |
[1,1,4,13,17,489,506,2007,6527,8534,245479,254013, 1007518,3276567,4284085,123230947,127515032, 505776043,1644843161,2150619204,61862180873, 64012800077,253900581104,825714543389, 1079615124493,31054938029193,32134553153686] |