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A322174
Primes that are not base-6 deletable primes (written in base 10).
1
7, 37, 43, 61, 151, 223, 229, 241, 271, 277, 307, 331, 337, 349, 367, 523, 691, 709, 733, 863, 907, 1009, 1033, 1051, 1069, 1103, 1109, 1123, 1223, 1231, 1249, 1283, 1289, 1297, 1301, 1303, 1321, 1327, 1381, 1423, 1429, 1447, 1471, 1483, 1531, 1549, 1567, 1597, 1621, 1627, 1657, 1663, 1741
OFFSET
1,1
COMMENTS
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 A322173.
LINKS
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[]]]]; Complement[Table[Prime[n], {n, PrimePi[Last[d]]}], d] (* Robert Price, Dec 06 2018 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Robert Price, Nov 29 2018
STATUS
approved