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A322443 Base-8 deletable primes (written in base 10). 2

%I

%S 2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,83,89,101,107,

%T 109,131,137,139,151,157,163,167,179,181,191,197,199,211,223,229,233,

%U 239,251,269,277,293,317,331,337,347,349,353,359,367,373,379,383,389,397,401,421,431,443,461,467,479,491

%N Base-8 deletable primes (written in base 10).

%C 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.

%C 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.

%H Robert Price, <a href="/A322443/b322443.txt">Table of n, a(n) for n = 1..566</a>

%t b = 8; d = {};

%t p = Select[Range[2, 10000], PrimeQ[#] &];

%t For[i = 1, i <= Length[p], i++,

%t c = IntegerDigits[p[[i]], b];

%t If[Length[c] == 1, AppendTo[d, p[[i]]]; Continue[]];

%t For[j = 1, j <= Length[c], j++,

%t t = Delete[c, j];

%t If[t[[1]] == 0, Continue[]];

%t If[MemberQ[d, FromDigits[t, b]], AppendTo[d, p[[i]]]; Break[]]]];

%t d (* _Robert Price_, Dec 08 2018 *)

%Y Cf. A080608, A080603, A096235-A096246.

%K nonn,base,easy

%O 1,1

%A _Robert Price_, Dec 08 2018

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Last modified June 12 22:55 EDT 2021. Contains 344978 sequences. (Running on oeis4.)