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A137848 Numbers k such that 10^k + 81 is prime. 1
2, 6, 8, 17, 22, 39, 89, 143, 167, 312, 334, 357, 414, 2254, 2694, 24094, 42081, 78632 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The next term, if one exists, is >100000. - Robert Price, Apr 25 2011
LINKS
EXAMPLE
10^2+81=100+81=181 is prime
MATHEMATICA
Select[10^Range[25000] + 81, PrimeQ] (* Alonso del Arte, Dec 27 2010 *)
PROG
(PARI) is(n)=ispseudoprime(10^n+81) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A279726 A337881 A331974 * A182629 A331972 A183212
KEYWORD
nonn
AUTHOR
EXTENSIONS
Added three terms: 2254,2694,24094. Robert Price, Oct 09 2010
a(17)=42081 from Robert Price, Dec 27 2010
a(18)=78632 from Robert Price, Mar 03 2011
STATUS
approved

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Last modified May 21 21:53 EDT 2024. Contains 372738 sequences. (Running on oeis4.)