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# User:Seth A. Troisi

Degree in Computer Science and Mathematics from Rose-Hulman.

Huge fan of Project Euler problem.

## Work on truncatable primes

See A024770 (right trunc), A024785 (left trunc), A077390 (left-right/bi trunc) In different bases: A076623 (total left) A076586 (total right),

See code on github at sethtroisi/OEIS/tree/master/A024770

## Work on A069675

I initially discovered A069675 as part of some Project Euler and took up the task of increasing the known bounds.
In 2016 time Charles R Greathouse IV and Robert Israel had calculated up to `a(300)`

. I've extended this to `a(434)`

.

My code can be found on GitHub at sethtroisi/OEIS/A069675.

I spent quite sometime trying to get a GPU based Rabin-Miller primality test to work but have been unsuccessful.

n | a(n) |
---|---|

1 | 1 * 10 ^ 0 + 2 = 2 |

2 | 1 * 10 ^ 0 + 3 = 3 |

3 | 1 * 10 ^ 0 + 5 = 5 |

4 | 1 * 10 ^ 0 + 7 = 7 |

5 | 1 * 10 ^ 1 + 1 = 11 |

100 | 7 * 10 ^ 12 + 9 |

150 | 6 * 10 ^ 45 + 1 |

200 | 5 * 10 ^ 175 + 3 |

250 | 5 * 10 ^ 757 + 9 |

300 | 7 * 10 ^ 2559 + 3 |

350 | 4 * 10 ^ 11293 + 3 |

400 | 7 * 10 ^ 38079 + 3 |

430 | 7 * 10 ^ 91215 + 3 |

431 | 9 * 10 ^ 91836 + 1 |

432 | 1 * 10 ^ 92691 + 9 |

433 | 4 * 10 ^ 94286 + 9 |

434 | 1 * 10 ^ 98288 + 3 |