A355035Consider the least base b >= 2 where the sum of digits of n is a prime number; a(n) corresponds to this prime number.
2, 2, 2, 2, 2, 3, 2, 2, 2, 3, 2, 3, 3, 3, 2, 2, …
The first 4 terms appear at position 4,902.
141592653589793238462643383279…
…32823066470938446095505822317253594081284811174502…
…862518983569485562099219222184272550254256887671790…
…0728354056704038674351362222477158915049530984448933…
…78150330102801200959972522222808014235710947603519255…
…724712724027616662968626222223166070448752292147150714…
…2049908652526026494219372222232392115625787249780316918…
…00895365146158452985143922222322021269349762489767362768…
…844169880089345618181766222223222323455584540767881356196…
…8441698800893456181817662222232223234555845407678813561963…
…84416988008934561818176622222322232345558454076788135619636…
…844169880089345618181766222223222323455584540767881356196361…
| terms | string | first position | occurrences |
|---|---|---|---|
| 1 | 2 | 6 | 100,002,410 |
| 2 | 22 | 135 | 10,005,081 |
| 3 | 222 | 1,735 | 999,612 |
| 4 | 2222 | 4,902 | 99,983 |
| 5 | 22222 | 65,260 | 9,953 |
| 6 | 222223 | 993,919 | 955 |
| 7 | 2222232 | 25,239,243 | 101 |
| 8 | 22222322 | 72,923,624 | 10 |
| 9 | 222223222 | 352,613,889 | 3 |
| 10 | 2222232223 | 352,613,889 | 2 |
| 11 | 22222322232 | 352,613,889 | 1 |
| 12 | 222223222323 | 352,613,889 | 1 |
Searched the first 1,000,000,000 digits. Strings longer than 12 digits are not indexed.