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 A096238 Number of n-digit base-5 deletable primes. 0
 2, 6, 14, 32, 69, 156, 377, 855, 2072, 5131, 12922, 32619, 83945, 217305, 571560, 1517012, 4056107 (list; graph; refs; listen; history; text; internal format)
 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. "Digit" means digit in base b. 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 = 5; a = {2}; d = {2, 3}; For[n = 2, n <= 8, n++,   p = Select[Range[b^(n - 1), b^n - 1], PrimeQ[#] &];   ct = 0;   For[i = 1, i <= Length[p], i++,    c = IntegerDigits[p[[i]], b];    For[j = 1, j <= n, j++,     t = Delete[c, j];     If[t[[1]] == 0, Continue[]];     If[MemberQ[d, FromDigits[t, b]], AppendTo[d, p[[i]]]; ct++;      Break[]]]];   AppendTo[a, ct]]; a (* Robert Price, Nov 12 2018 *) CROSSREFS Cf. A080608, A080603, A096235-A096246. Sequence in context: A217941 A346679 A232434 * A074878 A065495 A131352 Adjacent sequences:  A096235 A096236 A096237 * A096239 A096240 A096241 KEYWORD nonn,base,more AUTHOR Michael Kleber, Feb 28 2003 EXTENSIONS 12 more terms from Ryan Propper, Jul 19 2005 STATUS approved

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Last modified August 18 19:12 EDT 2022. Contains 356215 sequences. (Running on oeis4.)