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A096244 Number of n-digit base-11 deletable primes.

%I A096244 #12 Nov 14 2018 02:06:21
%S A096244 4,16,73,288,1117,4472,18120,74643,315174,1348936
%N A096244 Number of n-digit base-11 deletable primes.
%C A096244 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 A096244 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 A096244 b = 11; a = {4}; d = {2, 3, 5, 7};
%t A096244 For[n = 2, n <= 5, n++,
%t A096244   p = Select[Range[b^(n - 1), b^n - 1], PrimeQ[#] &];
%t A096244   ct = 0;
%t A096244   For[i = 1, i <= Length[p], i++,
%t A096244    c = IntegerDigits[p[[i]], b];
%t A096244    For[j = 1, j <= n, j++,
%t A096244     t = Delete[c, j];
%t A096244     If[t[[1]] == 0, Continue[]];
%t A096244     If[MemberQ[d, FromDigits[t, b]], AppendTo[d, p[[i]]]; ct++;
%t A096244      Break[]]]];
%t A096244   AppendTo[a, ct]];
%t A096244 a (* _Robert Price_, Nov 13 2018 *)
%Y A096244 Cf. A080608, A080603, A096235-A096246.
%K A096244 nonn,base,more
%O A096244 1,1
%A A096244 _Michael Kleber_, Feb 28 2003
%E A096244 5 more terms from _Ryan Propper_, Jul 19 2005