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%I #15 Oct 31 2024 06:46:50
%S 0,1,3,4,9,18,49,57,67,69,106,126,258,583,1221,1366,4311,11361,12621,
%T 14964,16017,22467,25434,45094,51051,89113
%N Numbers k such that 9^k + 10 is prime.
%C Contains exactly the halved even terms of A217137.
%t Select[Range[5000], PrimeQ[9^# + 10] &] (* _Vincenzo Librandi_, Oct 05 2012 *)
%o (PARI) is(n)=ispseudoprime(9^n+10) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A217137, A217347.
%K nonn,more,hard
%O 1,3
%A _Vincenzo Librandi_, Oct 05 2012
%E a(18)-a(26) added from the data at A217137 by _Amiram Eldar_, Jun 19 2022