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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 33 |
| 4 | 367 |
| 5 | 4844 |
| 6 | 71597 |
| 7 | 1147653 |
| 8 | 19559062 |
| 9 | 349766457 |
| 10 | 6502419671 |
| 11 | 124822220086 |
| 12 | 2461515013103 |
| 13 | 49668479230825 |
| 14 | 1022258042480874 |
| 15 | 21406231023989503 |
| 16 | 455112508356168561 |
| 17 | 9807294681518154334 |
| 18 | 213897254891041613995 |
| 19 | 4715809234441541498539 |
[1,1,4,33,367,4844,71597,1147653,19559062, 349766457,6502419671,124822220086,2461515013103, 49668479230825,1022258042480874,21406231023989503, 455112508356168561,9807294681518154334, 213897254891041613995,4715809234441541498539] |