A178175 Numbers n such that 10^n - 47 is prime.

2, 3, 6, 33, 48, 74, 231, 3206, 4544, 7064, 13634, 41384, 64862, 82790

Offset: 1

Author

Robert Price, Dec 17 2010

Keywords

• more
• nonn

Comments

The next term, if one exists, is >100000. - Robert Price, Apr 25 2011

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99953".

Examples

			10^3 - 47 = 953 is a prime number.
		

Links

• Makoto Kamada, List of near-repdigit-related prime numbers.
• Index entries for primes involving repunits.

Crossrefs

Cf. A108330, A108328.

Programs

Mathematica

m=1000; For[n=1, n
				

PARI

is(n)=ispseudoprime(10^n-47) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

a(12:14)=41384,64862,82790 from Robert Price, Apr 25 2011