A319596 -id:A319596 - cp's OEIS frontend

A320587 Primes that are not Base-3 deletable primes (written in base 10).

3, 13, 31, 37, 41, 43, 67, 79, 97, 103, 109, 113, 127, 131, 139, 149, 151, 157, 163, 193, 199, 211, 227, 229, 239, 241, 257, 271, 277, 281, 283, 293, 307, 311, 313, 331, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 433, 439, 443

Offset: 1

Robert Price, Nov 14 2018

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.
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.
Complement of all primes and A319596.

Robert Price, Table of n, a(n) for n = 1..906

Cf. A080608, A080603, A096235-A096246.

b = 3; d = {};
p = Select[Range[2, 10000], PrimeQ[#] &];
For[i = 1, i <= Length[p], i++,
  c = IntegerDigits[p[[i]], b];
  If[Length[c] == 1, AppendTo[d, p[[i]]]; Continue[]];
  For[j = 1, j <= Length[c], j++,
   t = Delete[c, j];
   If[t[[1]] == 0, Continue[]];
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 *)

Added the term 3. As pointed out by Kevin Ryde, there is no need to "seed" the list using base-2 assumptions. - Robert Price, Dec 06 2018

A321658 Primes that are not base-4 deletable primes (written in base 10).

Original entry on oeis.org

5, 17, 37, 41, 73, 89, 97, 101, 131, 137, 149, 193, 199, 233, 257, 277, 281, 293, 313, 337, 347, 349, 353, 367, 373, 379, 389, 401, 409, 421, 521, 569, 577, 593, 601, 613, 617, 641, 661, 673, 677, 683, 761, 769, 809, 811, 823, 829, 853, 857, 859, 929, 937

Offset: 1

Robert Price, Nov 15 2018

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.
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.
Complement of all primes and A319596.

Robert Price, Table of n, a(n) for n = 1..3741

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

b = 4; d = {};
p = Select[Range[2, 10000], PrimeQ[#] &];
For[i = 1, i <= Length[p], i++,
  c = IntegerDigits[p[[i]], b];
  If[Length[c] == 1, AppendTo[d, p[[i]]]; Continue[]];
  For[j = 1, j <= Length[c], j++,
   t = Delete[c, j];
   If[t[[1]] == 0, Continue[]];
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 *)

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A320587 Primes that are not Base-3 deletable primes (written in base 10).

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