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 A321596 Primes that are not Base-2 deletable primes (written in base 10). 1

%I

%S 17,31,41,67,71,89,97,103,113,127,131,139,181,191,193,199,223,227,233,

%T 239,241,251,257,263,269,271,283,337,353,367,373,379,383,401,409,431,

%U 433,439,443,449,463,479,487,491,499,503,509,521,523,541,547,571,577

%N Primes that are not Base-2 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. However, in base 2 we adopt the convention that 2 = 10 and 3 = 11 are deletable.

%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 A096246.

%H Robert Price, <a href="/A321596/b321596.txt">Table of n, a(n) for n = 1..2351</a>

%t d = {2, 3};

%t For[n = 3, n <= 15, n++,

%t p = Select[Range[2^(n - 1), 2^n - 1], PrimeQ[#] &];

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

%t c = IntegerDigits[p[[i]], 2];

%t For[j = 1, j <= n, j++,

%t t = Delete[c, j];

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

%t If[MemberQ[d, FromDigits[t, 2]], AppendTo[d, p[[i]]]; Break[]]]]]; Complement[Table[Prime[n], {n, PrimePi[Last[d]]}], d]

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

%K nonn,base,easy

%O 1,1

%A _Robert Price_, Nov 14 2018

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Last modified September 24 04:10 EDT 2020. Contains 337316 sequences. (Running on oeis4.)