A108364 Integers k such that 10^k - 33 is prime.

2, 3, 4, 10, 18, 46, 48, 121, 154, 158, 170, 196, 211, 250, 294, 316, 320, 663, 975, 1165, 1351, 4126, 4270, 5724, 7156, 15025, 19132, 25035, 36174, 77418

Offset: 1

Author

Parthasarathy Nambi, Jul 01 2005

Keywords

• nonn
• more

Comments

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99967".

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

Examples

			k=2 is a term because 10^2 - 33 = 67 (prime).
k=48 is a term because 10^48 - 33 = 999999999999999999999999999999999999999999999967 (prime).
		

Links

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

Crossrefs

Cf. A108330, A108328.

Programs

Mathematica

For[n = 1, n < 1000, n++, If[PrimeQ[10^n - 33], Print[n]]] (Steinerberger)

Extensions

a(8)-a(21) from Stefan Steinerberger, Jan 28 2006

a(22)-a(29) extracted from Makoto Kamada website by Robert Price, Dec 06 2010

Edited by Ray Chandler, Dec 23 2010

a(30) from Robert Price, Apr 25 2011