%I A037055
%S A037055 13,11,1117,10111,101111,1111151,11110111,101111111,1111111121,
%T A037055 11111111113,101111111111,1111111118111,11111111111411,111111111116111,
%U A037055 1111111111111181,11111111101111111,101111111111111111
%N A037055 Smallest prime containing exactly n 1's.
%C A037055 Except for the initial term, A037055 is conjectured to be identical to 
               A084673. - Robert G. Wilson v (rgwv(AT)rgwv.com), Jul 04 2003
%t A037055 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, 1], {n, 1, 18}]
%Y A037055 Cf. A084673, A065584, A065821, A037054, A034388, A036507-A036536.
%Y A037055 Cf. A037053, A037057, A037059, A037061, A037063, A037065, A037067, A037069, 
               A037071.
%Y A037055 Sequence in context: A083229 A140554 A002591 this_sequence A022969 A023455 
               A055124
%Y A037055 Adjacent sequences: A037052 A037053 A037054 this_sequence A037056 A037057 
               A037058
%K A037055 nonn,base
%O A037055 1,1
%A A037055 Patrick De Geest (pdg(AT)worldofnumbers.com), Jan 04 1999.
%E A037055 More terms from Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Feb 10 
               2003
%E A037055 Edited by Robert G. Wilson v (rgwv(AT)rgwv.com), Jul 04 2003