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A322476
Primes that are not base-11 deletable primes (written in base 10).
1
11, 17, 19, 53, 67, 89, 97, 103, 107, 109, 127, 131, 137, 139, 157, 163, 173, 179, 181, 191, 193, 197, 199, 223, 227, 229, 239, 241, 269, 277, 281, 307, 311, 379, 383, 397, 401, 419, 421, 431, 443, 449, 463, 467, 491, 499, 503, 541, 547, 569, 571, 577, 587, 593, 599, 601, 607, 613
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 A322475.
LINKS
MATHEMATICA
b = 11; 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 09 2018 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Robert Price, Dec 09 2018
STATUS
approved