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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.

Image: 50 pixels
Select entries from A069675
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