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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 233 |
| 3 | 5557 |
| 4 | 47777 |
| 5 | 11111111113 |
| 6 | 1131313131313 |
| 7 | 171717173171717 |
| 8 | 19191919191981919 |
| 9 | 1232323232323232323 |
| 10 | 292929292929292929929 |
| 11 | 31313131313131313123131 |
| 12 | 3713737373737373737373737 |
| 13 | 414141414141414141241414141 |
| 14 | 43434343434343943434343434343 |
| 15 | 4714747474747474747474747474747 |
[2,233,5557,47777,11111111113,1131313131313, 171717173171717,19191919191981919, 1232323232323232323,292929292929292929929, 31313131313131313123131,3713737373737373737373737, 414141414141414141241414141, 43434343434343943434343434343, 4714747474747474747474747474747] |