A135131 Integers n such that 10^n + 79 is a prime number.

1, 2, 4, 7, 16, 18, 43, 60, 73, 91, 106, 115, 120, 169, 394, 444, 516, 835, 886, 1912, 3120, 3602, 5664, 10188, 14434, 16564, 23732, 29058, 47728, 63916

Offset

1,2

Comments

If any additional terms exist, they are >40000. - Robert Price, Sep 25 2010

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10079".

Links

Table of n, a(n) for n=1..30.

Makoto Kamada, List of near-repdigit-related prime numbers.

Index entries for primes involving repunits.

Example

7 is a member because 10^7+79 = 10000000+79 = 10000079, which is a prime number.

Mathematica

Select[Range[1000], PrimeQ[10^# + 79] &] (* G. C. Greubel, Sep 28 2016 *)

Crossrefs

Cf. A095688, A108052, A108050, A108312, A107083, A108049, A108054.

Sequence in context: A030033 A364596 A280031 * A032363 A303749 A239390

Adjacent sequences: A135128 A135129 A135130 * A135132 A135133 A135134

Keyword

more,nonn

Author

Julien Peter Benney (jpbenney(AT)gmail.com), Feb 12 2008

Extensions

Added two terms: 10188 and 14434. Robert Price, Mar 22 2010

Added seven terms: 1912, 3120, 3602, 5664, 16564, 23732, 29058. Robert Price, Sep 25 2010

Edited by Ray Chandler, Dec 23 2010

a(29)=47728 from Robert Price, Dec 31 2010

a(30)=63916 from Robert Price, Jan 29 2011

Status

approved