1,1

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, 9], {n, 1, 20}]

Cf. A065592, A065582, A037070, A034388, A036507-A036536.

Cf. A037053, A037055, A037057, A037059, A037061, A037063, A037065, A037067, A037069.

Sequence in context: A147830 A135162 A067272 this_sequence A065582 A055558 A160452

Adjacent sequences: A037068 A037069 A037070 this_sequence A037072 A037073 A037074

nonn,base

Patrick De Geest (pdg(AT)worldofnumbers.com), Jan 04 1999.

More terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Jan 10 2002