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A123372 Numbers n such that 10*(11*10^n - 1) + 1 is prime. 0
0, 1, 29, 71, 95, 173, 298, 4937, 4982, 15755, 16639, 17621 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
EXAMPLE
a(1) = 0; 101 is prime.
a(2) = 1; 1091 is prime.
a(3) = 29; 10999999999999999999999999999991 is prime.
MATHEMATICA
Select[Range[0, 1000], PrimeQ[10*(11*10^#-1)+1]&]
PROG
(PARI) g(n, m=1) = for(x=1, n, y=10*(11*10^x-1)+m; if(ispseudoprime(y), print1(x", ")))
CROSSREFS
Sequence in context: A165945 A226892 A183194 * A031343 A155483 A141891
KEYWORD
hard,more,nonn
AUTHOR
Cino Hilliard, Oct 12 2006
EXTENSIONS
0 inserted and a(10)-a(12) from Ryan Hitchman, Sep 13 2017
STATUS
approved

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Last modified May 25 17:00 EDT 2024. Contains 372804 sequences. (Running on oeis4.)