%I A037069
%S A037069 83,881,8887,88883,888887,28888883,88888883,888888883,48888888883,
%T A037069 288888888889,888888888887,48888888888883,88888888888889,
%U A037069 888888888888883,18888888888888883,88888888888888889
%N A037069 Smallest prime containing exactly n 8's.
%t A037069 f[n_, b_] := Block[{k = 10^(n + 1), p = Permutations[ Join[ Table[b,
{i, 1, n}], {x}]], c = Complement[Table[j, {j, 0, 9}], {b}], q =
{}}, Do[q = Append[q, Replace[p, x -> c[[i]], 2]], {i, 1, 9}]; r
= Min[ Select[ FromDigits /@ Flatten[q, 1], PrimeQ[ # ] & ]]; If[r
? Infinity, r, p = Permutations[ Join[ Table[ b, {i, 1, n}], {x,
y}]]; q = {}; Do[q = Append[q, Replace[p, {x -> c[[i]], y -> c[[j]]},
2]], {i, 1, 9}, {j, 1, 9}]; Min[ Select[ FromDigits /@ Flatten[q,
1], PrimeQ[ # ] & ]]]]; Table[ f[n, 8], {n, 1, 18}]
%Y A037069 Cf. A065591, A037068, A034388, A036507-A036536.
%Y A037069 Cf. A037053, A037055, A037057, A037059, A037061, A037063, A037065, A037067,
A037071.
%Y A037069 Sequence in context: A112766 A128950 A068851 this_sequence A103233 A093283
A156924
%Y A037069 Adjacent sequences: A037066 A037067 A037068 this_sequence A037070 A037071
A037072
%K A037069 nonn,base,easy
%O A037069 1,1
%A A037069 Patrick De Geest (pdg(AT)worldofnumbers.com), Jan 04 1999.
%E A037069 Corrected by Jud McCranie (j.mccranie(AT)comcast.net), Jan 04 2001. More
terms from Erich Friedman (efriedma(AT)stetson.edu), Jun 03 2001.
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