A248350 Numbers n such that 10^n - 123456789 is prime.

9, 10, 13, 19, 26, 68, 73, 115, 190, 195, 232, 549, 742, 1502, 2239, 2618, 5143, 8081, 9442, 31402, 77919, 93790, 99434, 120841

Offset: 1

Author

Derek Orr, Oct 05 2014

Keywords

• nonn
• hard
• more

Comments

a(26) > 200000. - Robert Price, Jun 06 2020

Crossrefs

Cf. A248349, A248351, A248352, A050289.

Programs

PARI

for(n=1,10^4,if(ispseudoprime(10^n - 123456789),print1(n,", ")))

Extensions

a(21)-a(25) from Robert Price, Feb 26 2020