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A171227 Numbers k such that 9 + 10^k + 9*100^k is prime. 0
0, 1, 4, 17, 26, 28, 47, 70, 91, 1129, 4334, 12347 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
No more terms up to k = 4100.
LINKS
EXAMPLE
19, 919, 900010009 are prime so that 0, 1 and 4 are terms.
PROG
(PARI) is(n)=ispseudoprime(9+10^n+9*100^n) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Cf. A083816.
Sequence in context: A273022 A273119 A302618 * A061387 A366210 A335593
KEYWORD
more,nonn
AUTHOR
Jason Earls, Dec 05 2009
EXTENSIONS
a(11)-a(12) from Michael S. Branicky, Jun 22 2023
STATUS
approved

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Last modified February 27 07:37 EST 2024. Contains 370367 sequences. (Running on oeis4.)