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A108364 Integers n such that 10^n - 33 is prime. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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. [From Robert Price, Apr 25 2011]

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

If n=2 then 10^n - 33 = 67 (prime).

If n=48 then 10^n - 33 = 999999999999999999999999999999999999999999999967 (prime).

MATHEMATICA

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

CROSSREFS

Cf. A108330, A108328.

Sequence in context: A007661 A049891 A135432 * A145028 A229545 A085932

Adjacent sequences:  A108361 A108362 A108363 * A108365 A108366 A108367

KEYWORD

more,nonn

AUTHOR

Parthasarathy Nambi, Jul 01 2005

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)=77418 from Robert Price, Apr 25 2011

STATUS

approved

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Last modified December 3 21:14 EST 2016. Contains 278745 sequences.