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A108327
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Integers n such that 10^n-21 is a prime number.
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2
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OFFSET
| 1,1
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COMMENTS
| See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable/proven prime - search on "99979".
No other terms <100,000. - [From Robert Price (pamandbobprice(AT)yahoo.com), March 3 2011]
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LINKS
| Makoto Kamada, List of near-repdigit-related prime numbers.
Index entries for primes involving repunits.
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EXAMPLE
| 6 is a member because 10^6-21 = 1000000-21 = 999979, which is prime.
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CROSSREFS
| Cf. A089675, A095714, A092767.
Sequence in context: A203901 A190958 A109243 * A196010 A121071 A092199
Adjacent sequences: A108324 A108325 A108326 * A108328 A108329 A108330
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KEYWORD
| more,nonn
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AUTHOR
| Julien Peter Benney (jpbenney(AT)ftml.net), Jun 30 2005
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EXTENSIONS
| Edited by Ray Chandler (rayjchandler(AT)sbcglobal.net), Dec 23 2010
a(10)=53558 from Robert Price (pamandbobprice(AT)yahoo.com), Mar 03 2011
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