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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A321596 Primes that are not base-2 deletable primes (written in base 10).

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%I A321596 #14 Apr 14 2021 01:17:52
%S A321596 17,31,41,67,71,89,97,103,113,127,131,139,181,191,193,199,223,227,233,
%T A321596 239,241,251,257,263,269,271,283,337,353,367,373,379,383,401,409,431,
%U A321596 433,439,443,449,463,479,487,491,499,503,509,521,523,541,547,571,577
%N A321596 Primes that are not base-2 deletable primes (written in base 10).
%C A321596 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. However, in base 2 we adopt the convention that 2 = 10 and 3 = 11 are deletable.
%C A321596 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 A321596 Complement of all primes and A096246.
%H A321596 Robert Price, <a href="/A321596/b321596.txt">Table of n, a(n) for n = 1..2351</a>
%t A321596 d = {2, 3};
%t A321596 For[n = 3, n <= 15, n++,
%t A321596   p = Select[Range[2^(n - 1), 2^n - 1], PrimeQ[#] &];
%t A321596   For[i = 1, i <= Length[p], i++,
%t A321596    c = IntegerDigits[p[[i]], 2];
%t A321596    For[j = 1, j <= n, j++,
%t A321596     t = Delete[c, j];
%t A321596     If[t[[1]] == 0, Continue[]];
%t A321596     If[MemberQ[d, FromDigits[t, 2]], AppendTo[d, p[[i]]];  Break[]]]]]; Complement[Table[Prime[n], {n, PrimePi[Last[d]]}], d]
%Y A321596 Cf. A080608, A080603, A096235-A096246.
%K A321596 nonn,base,easy
%O A321596 1,1
%A A321596 _Robert Price_, Nov 14 2018