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A322475
Base-11 deletable primes (written in base 10).
2
2, 3, 5, 7, 13, 23, 29, 31, 37, 41, 43, 47, 59, 61, 71, 73, 79, 83, 101, 113, 149, 151, 167, 211, 233, 251, 257, 263, 271, 283, 293, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 389, 409, 433, 439, 457, 461, 479, 487, 509, 521, 523, 557, 563, 631, 653, 659, 673, 677, 719, 733, 739
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.
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[]]]];
d (* Robert Price, Dec 09 2018 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Robert Price, Dec 09 2018
STATUS
approved