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%I #18 May 03 2024 15:42:01
%S 1,2,3,4,5,15,35,61,256,357,628,767,1064,1096,6608,14821,15341,18795,
%T 22648,24199,31919,38519,44279
%N Numbers k such that 4*10^k - 11 is prime.
%C Numbers corresponding to terms <= 767 are certified primes. - _Klaus Brockhaus_, Feb 16 2005
%C The next term is larger than 2500. - _Stefan Steinerberger_, Feb 18 2006
%t For[n=1, n<2500,n++,If[PrimeQ[4*10^n-11], Print[n]]] (* _Stefan Steinerberger_, Feb 18 2006 *)
%o (PARI) is(n)=ispseudoprime(4*10^n-11) \\ _Charles R Greathouse IV_, Jun 13 2017
%K more,nonn
%O 1,2
%A Tom Mueller (muel4503(AT)uni-trier.de), Feb 08 2005
%E a(9)-a(14) from _Klaus Brockhaus_, Feb 16 2005
%E a(15) from _Ryan Propper_, Jul 21 2006
%E a(16)-a(17) from _Michael S. Branicky_, May 01 2023
%E a(18)-a(23) from Kamada data by _Tyler Busby_, May 03 2024