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A110983 Integers n such that 5*10^n + 51 is prime. 0
1, 3, 4, 16, 430, 727, 1415, 2691, 3160, 3904, 5464, 19875, 65255, 68524 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "50051".

a(15) > 10^5. - Robert Price, Jan 28 2017

LINKS

Table of n, a(n) for n=1..14.

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

Index entries for primes involving repunits.

EXAMPLE

n = 4 is a member because: 5*10^4+51 = 5*10000+51 = 50000+51 = 50051, which is prime.

MATHEMATICA

Select[Range[1, 1000], PrimeQ[5*10^# + 51] &] (* Julien Kluge, Dec 15 2016 *)

CROSSREFS

Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054.

Sequence in context: A353155 A252606 A248240 * A100560 A025534 A082000

Adjacent sequences:  A110980 A110981 A110982 * A110984 A110985 A110986

KEYWORD

more,nonn

AUTHOR

Julien Peter Benney (jpbenney(AT)ftml.net), Oct 04 2005

EXTENSIONS

a(11)-a(12) from Ray Chandler, Dec 23 2010

Prepended a(1)=1 by Robert Price, Jan 28 2017

a(13)-a(14) from Robert Price, Jan 28 2017

STATUS

approved

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Last modified August 9 21:08 EDT 2022. Contains 356026 sequences. (Running on oeis4.)