%I #12 Nov 14 2018 02:06:21
%S 4,16,73,288,1117,4472,18120,74643,315174,1348936
%N Number of n-digit base-11 deletable primes.
%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. "Digit" means digit in base b.
%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.
%t b = 11; a = {4}; d = {2, 3, 5, 7};
%t For[n = 2, n <= 5, n++,
%t p = Select[Range[b^(n - 1), b^n - 1], PrimeQ[#] &];
%t ct = 0;
%t For[i = 1, i <= Length[p], i++,
%t c = IntegerDigits[p[[i]], b];
%t For[j = 1, j <= n, j++,
%t t = Delete[c, j];
%t If[t[[1]] == 0, Continue[]];
%t If[MemberQ[d, FromDigits[t, b]], AppendTo[d, p[[i]]]; ct++;
%t Break[]]]];
%t AppendTo[a, ct]];
%t a (* _Robert Price_, Nov 13 2018 *)
%Y Cf. A080608, A080603, A096235-A096246.
%K nonn,base,more
%O 1,1
%A _Michael Kleber_, Feb 28 2003
%E 5 more terms from _Ryan Propper_, Jul 19 2005
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