

A322173


Base6 deletable primes (written in base 10).


2



2, 3, 5, 11, 13, 17, 19, 23, 29, 31, 41, 47, 53, 59, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 227, 233, 239, 251, 257, 263, 269, 281, 283, 293, 311, 313, 317, 347, 353, 359, 373, 379, 383, 389, 397
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OFFSET

1,1


COMMENTS

A prime p is a baseb 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.


LINKS

Robert Price, Table of n, a(n) for n = 1..3561


MATHEMATICA

b = 6; 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[]]]];
d (* Robert Price, Dec 06 2018 *)


CROSSREFS

Cf. A080608, A080603, A096235A096246.
Sequence in context: A275059 A072538 A225856 * A216509 A075237 A040062
Adjacent sequences: A322170 A322171 A322172 * A322174 A322175 A322176


KEYWORD

nonn,base,easy


AUTHOR

Robert Price, Nov 29 2018


STATUS

approved



