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Primes that are not base-4 deletable primes (written in base 10).
1

%I #17 Dec 07 2018 12:27:16

%S 5,17,37,41,73,89,97,101,131,137,149,193,199,233,257,277,281,293,313,

%T 337,347,349,353,367,373,379,389,401,409,421,521,569,577,593,601,613,

%U 617,641,661,673,677,683,761,769,809,811,823,829,853,857,859,929,937

%N Primes that are not base-4 deletable primes (written in base 10).

%C A prime p is a base-b deletable prime if when written in base b it has the property that removing some digit leaves either the empty string or another deletable prime.

%C Deleting a digit cannot leave any leading zeros in the new string. For example, deleting the 2 in 2003 to obtain 003 is not allowed.

%C Complement of all primes and A319596.

%H Robert Price, <a href="/A321658/b321658.txt">Table of n, a(n) for n = 1..3741</a>

%t b = 4; d = {};

%t p = Select[Range[2, 10000], PrimeQ[#] &];

%t For[i = 1, i <= Length[p], i++,

%t c = IntegerDigits[p[[i]], b];

%t If[Length[c] == 1, AppendTo[d, p[[i]]]; Continue[]];

%t For[j = 1, j <= Length[c], j++,

%t t = Delete[c, j];

%t If[t[[1]] == 0, Continue[]];

%t If[MemberQ[d, FromDigits[t, b]], AppendTo[d, p[[i]]]; Break[]]]]; Complement[Table[Prime[n], {n, PrimePi[Last[d]]}], d] (* _Robert Price_, Dec 06 2018 *)

%Y Cf. A080608, A080603, A096235-A096246, A321657.

%K nonn,base,easy

%O 1,1

%A _Robert Price_, Nov 15 2018