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%I #28 Feb 03 2024 00:50:01
%S 1,2,5,7,8,10,13,14,17,19,22,23,26,34,35,37,38,40,41,43,44,47,49,50,
%T 56,59,61,65,70,71,73,76,80,82,83,85,91,92,100,101,103,104,106,110,
%U 112,122,124,125,127,128,131,139,140,142,143,145,148,149,154,155,157,160,161
%N Numbers k such that 10*k + 9 is prime.
%H Daniel Starodubtsev, <a href="/A102700/b102700.txt">Table of n, a(n) for n = 1..10000</a>
%H Chris Caldwell, <a href="http://www.utm.edu/research/primes/lists/small/1000.txt">The first 1,000 primes</a>.
%e 10*1 + 9 = 19 (prime);
%e 10*40 + 9 = 409 (prime);
%e 10*70 + 9 = 709 (prime).
%t Select[Range[0, 170], PrimeQ[10# + 9] &] (* _Ray Chandler_, Nov 07 2006 *)
%o (Magma) [n: n in [0..3000]| IsPrime(10*n+9)]; // _Vincenzo Librandi_, Apr 06 2011
%o (PARI) is(n)=isprime(10*n+9) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A030433, A049510.
%K base,nonn
%O 1,2
%A _Parthasarathy Nambi_, Feb 04 2005
%E Edited and extended by _Ray Chandler_, Nov 07 2006