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A322172 Primes that are not base-7 deletable primes (written in base 10).

%I A322172 #13 Dec 07 2018 12:27:25
%S A322172 7,11,13,29,43,53,59,61,67,71,73,79,83,89,97,107,109,113,127,151,157,
%T A322172 173,179,181,193,197,211,229,239,257,269,271,277,281,283,307,337,347,
%U A322172 349,353,359,367,373,379,383,389,397,401,409,419,421,431,433,439,443,449,457,461,463,467,479,487,491,499
%N A322172 Primes that are not base-7 deletable primes (written in base 10).
%C A322172 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 A322172 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 A322172 Complement of all primes and A321910.
%H A322172 Robert Price, <a href="/A322172/b322172.txt">Table of n, a(n) for n = 1..10286</a>
%t A322172 b = 7; d = {};
%t A322172 p = Select[Range[2, 10000], PrimeQ[#] &];
%t A322172 For[i = 1, i <= Length[p], i++,
%t A322172   c = IntegerDigits[p[[i]], b];
%t A322172   If[Length[c] == 1, AppendTo[d, p[[i]]]; Continue[]];
%t A322172   For[j = 1, j <= Length[c], j++,
%t A322172    t = Delete[c, j];
%t A322172    If[t[[1]] == 0, Continue[]];
%t A322172 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 A322172 Cf. A080608, A080603, A096235-A096246, A321657.
%K A322172 nonn,base,easy
%O A322172 1,1
%A A322172 _Robert Price_, Nov 29 2018