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%I #19 Mar 15 2023 10:50:33
%S 11,19,29,31,41,59,61,71,79,89,101,109,139,149,151,181,191,199,239,
%T 251,269,281,349,401,409,421,439,449,491,499,509,521,569,599,601,691,
%U 701,709,739,751,769,809,821,839,881,991,1009,1021,1039,1049,1051,1069
%N Prime numbers that cannot become prime by chopping off any of the initial consecutive digits.
%H Harvey P. Dale, <a href="/A196095/b196095.txt">Table of n, a(n) for n = 1..1000</a>
%e 139 qualifies because neither 9 nor 39 is prime
%t Select[Prime[Range[200]], Union[PrimeQ[Table[Mod[#, 10^i], {i, Floor[Log[10, #]]}]]] == {False} &] (* _T. D. Noe_, Sep 27 2011 *)
%t cbpQ[n_]:=NoneTrue[Table[FromDigits[Drop[IntegerDigits[n],i]],{i, IntegerLength[ n]-1}],PrimeQ]; Select[Prime[Range[5,200]],cbpQ] (* The program uses the NoneTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Aug 27 2014 *)
%K nonn,base
%O 1,1
%A _J. Lowell_, Sep 27 2011
%E More terms from _T. D. Noe_, Sep 27 2011