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A135117 Integers k such that 10^k + 87 is a prime number. 1
1, 3, 9, 19, 39, 43, 121, 153, 1243, 14445, 15273, 26779 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

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 "10087".

LINKS

Table of n, a(n) for n=1..12.

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

Index entries for primes involving repunits.

EXAMPLE

3 is a term because 10^3 + 87 = 1000 + 87 = 1087, which is a prime number.

CROSSREFS

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

Sequence in context: A115238 A005994 A080010 * A038163 A327381 A146819

Adjacent sequences:  A135114 A135115 A135116 * A135118 A135119 A135120

KEYWORD

nonn,more

AUTHOR

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

EXTENSIONS

Term 14445 from Robert Price, Mar 22 2010

Terms 1243, 15273, 26779 from Robert Price, Oct 04 2010

Edited by Ray Chandler, Dec 23 2010

STATUS

approved

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Last modified June 30 10:15 EDT 2022. Contains 354922 sequences. (Running on oeis4.)