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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 31 |
| 3 | 653 |
| 4 | 4159 |
| 5 | 14159 |
| 6 | 314159 |
| 7 | 1592653 |
| 8 | 28841971 |
| 9 | 795028841 |
| 10 | 5926535897 |
| 11 | 93238462643 |
| 12 | 141592653589 |
| 13 | 9265358979323 |
| 14 | 23846264338327 |
| 15 | 841971693993751 |
| 16 | 8628034825342117 |
| 17 | 89793238462643383 |
| 18 | 348253421170679821 |
| 19 | 3832795028841971693 |
| 20 | 89793238462643383279 |
[3,31,653,4159,14159,314159,1592653,28841971, 795028841,5926535897,93238462643,141592653589, 9265358979323,23846264338327,841971693993751, 8628034825342117,89793238462643383, 348253421170679821,3832795028841971693, 89793238462643383279] |